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On Sunday, after the Cubs lost to the Red Sox in Boston in the long-awaited rematch of the curse-tastic 1918 World Series, the interleague ledger for the National League Central looked like this:

Chicago Cubs


Cincinnati Reds


Houston Astros


Milwaukee Brewers


Pittsburgh Pirates


St. Louis Cardinals


The Brewers' 3-0 mark isn't technically "interleague," as their trio of victories came against the National League's Colorado Rockies. The series, however, took place during MLB's interleague schedule (i.e., the six three-game series set aside for interleague play), making it as separate from the balanced, 144-game non-interleague schedule as any matchups against the American League.

The biggest complaint about interleague play is that it drastically unbalances the schedule. Sure, many people dislike interleague because of the tradition element, but if that were its only drawback, the criticisms wouldn't have much traction (much like those directed toward the wild card). The fact is that a six-series mini-schedule where the leagues cross in such a way that each division plays another division in the opposite league (along with their designated "natural rivalries") can be nothing but uneven.

Teams play between four and six other teams they would never face regularly, and they are never exactly the same teams that their division-mates face. If one club happens to have a full slate of sub-.500 teams on its schedule while their division rival's is filled with teams ten games over .500, there is nothing that can be done; the team with the easier schedule is given a great advantage.

How have these scheduling quirks affected the National League Central? Will the division, which many predicted to finish in a tight cluster, be turned on the unbalanced nature of this year's 2011 interleague schedule? Below are the division's six teams, ranked by difficulty of interleague schedule (including the NL-vs.-NL games the various teams use to fill in the schedule).

6. Milwaukee Brewers
Opponents: at Boston, at New York Yankees, at Minnesota*, vs. Minnesota*, vs. Tampa Bay, vs. Colorado
Opponents’ winning percentage (at start of interleague): .486

Heading into the season, this interleague schedule looked like it could be the toughest of the division. The Brewers are the only team in the entire division to be stuck facing the American League East's top three teams, the Red Sox, Yankees, and Rays. It's still a tough slate. What brings Milwaukee's opponents' winning percentage down so low is the horrific record of the Minnesota Twins. At 15-27 heading into interleague season, the Twins had the second-worst record in baseball. The Brewers benefit greatly from being able to play that team six times when no other Central team does even once.

5. Chicago Cubs
Opponents: at Boston, at Kansas City, at Chicago White Sox*, vs. San Francisco, vs. Chicago White Sox*, vs. New York Yankees
Opponents’ winning percentage: .502

The Cubs are in a boat similar to the Brewers’. With the Red Sox, Yankees, and world-champion Giants on their schedule, their opponents looked to be rather formidable at the start of the season. The White Sox, however, have decided to play rather poorly this season. With six games against that .444 winning percentage—a record "bested" only by the Twins among NL Central interleague opponents—the Cubs have caught some luck. Of course, if the White Sox or Twins ever improve to anything near their preseason predictions, that luck will get wiped away.

4. Houston Astros
Opponents: at Toronto, at Los Angeles, at Texas*, vs. Texas*, vs. Tampa Bay, vs. Boston
Opponents’ winning percentage: .517

The Rays, Red Sox, and two series against the Rangers: that's certainly a much tougher draw than a team with the worst record in all of baseball would like to see. With the Royals also playing better baseball than most predicted, it's even less inviting. Astros fans can be happy that the Red Sox have yet to break things wide open (like they were predicted to) and that the team will be hosting an extra series against the Dodgers during interleague.

3. Pittsburgh Pirates
Opponents: at Toronto, at Cleveland, at Washington, vs. Boston, vs. Detroit, vs. Baltimore
Opponents’ winning percentage: .518

At first glance, Pittsburgh's slate of Baltimore, Cleveland, and Washington seems pretty easy. The Indians, however, continue to maintain the sport's top record, tipping the Pirates towards the top half of the list.

2. St. Louis Cardinals
Opponents: at Baltimore, at Tampa Bay, at Kansas City*, vs. Kansas City*, vs. Toronto, vs. Philadelphia
Opponents’ winning percentage: .519

The Cardinals suffer from the distinction of playing their interleague schedule against the most "good" teams. Of the five teams the Cardinals play, they only face one team with a worse record than Kansas City who, at the start of interleague, had a 21-22 record – the 19-23 Orioles. Every other team in the division faces at least one team with a worse record. Their interleague National League opponent also happens to be the Phillies, who own the NL's best record. Not an easy draw.

1. Cincinnati Reds
Opponents: at Baltimore, at Tampa Bay, at Cleveland*, vs. Cleveland*, vs. New York Yankees, vs. Toronto
Opponents’ winning percentage: .557

If it weren't for the misfortune of Cincinnati's "natural rival," the Reds would be much more solidly middle-of-the-pack. As it is, the Reds are forced to play six games against the best record in baseball. If the Indians really are as good as their 26-15 record would indicate, a slate of games against the Rays, Indians, Blue Jays, and Yankees will be tough to overcome for the division leader.

Pre-season predictions, here at Baseball Prospectus and just about everywhere else, saw the NL Central as a three-team race between the Reds, Cardinals, and Brewers. Today's standings show that the division is shaking out to be just that, with the Cardinals holding a two-game lead at the moment. But the interleague schedule has yet to fully start. This weekend's games were only an appetizer; the full complement of games doesn’t begin until June 17. With the Cards and Reds facing the division's toughest slate and the Brewers facing the easiest, that final, close finish could very well be affected. Based on winning percentage, the Reds’ opponents are currently favored to win 10 of the 18 interleague games. The Brewers, on the other hand, are expected to win 10 themselves. A two-game switch like that could easily mean a one- or two-place difference in the final standings if the teams stay as even as some have predicted.

The unbalanced nature of interleague play is a fact of life in today's game. Considering the effects the Brewers/Twins, Cubs/White Sox, and Red/Indians pairings have had on these rankings, it should be noted that the "natural rivalries" are the biggest reasons for this. Interleague play likely won't be going away any time soon, so it's important to recognize how the unbalanced schedule could potentially affect playoff races from year to year. If, for example, the Brewers really do gain two games on their division rivals in a tight race, they may have their very beneficial interleague schedule to thank.

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If The Cardinals win the division by 2 games, this weekend series sweep of the Reds by the Indians will be pivotal. Which sucks. The worst part is that nobody whop matters seems to give a damn. Joe Sheehan in his newsletter this weekend essential threw up his hands in disgust about the situation.
Slightly off topic, but I want to apologize to the readers for using the Indians logo. I love the Indians as a team and an organization and think very highly of many who play and work there, but that mascot is an ugly relic of the past and has to go.
As a Cleveland Indians fan living in a town predominately Native American I can sympathize. I love the organization, its staff, and players but hate not being able to wear the majority of their apparel.

Chief Wahoo needed to go decades ago. Most of the Natives where I live don't even have a problem with the team name just that stupid Chief Wahoo logo! Get rid of it switch to the stylized I and put this all behind us.
Agreed. Next step is to take the image down, right?
This article sums up why interleague play is held in low regard by at least some baseball fans. One of the great things about the "traditional" baseball schedule was that teams in the same league or division always played the same opponents and played them the same number of games each season. At least as much as was possible before expansion created too many opponents for this to be really feasible. Now, thanks to interleague play and the requirement that "traditional rivals" play every season, this is no longer the case. In a sport that plays nearly every day for six months and often finds pennant races decided by a game or two, this uneven scheduling is inherently unfair. To refer back to the article, the Reds will play their 18 interleague games against opponents with a projected winning percentage of .557 while the Brewers opponents for the same group of games has a projected percentage of .486. This is a huge difference for the Reds to have to make up over the remainder of the schedule (yes, I understand that it really isn't as simple as this example).
I agree with the overall thoughts in your comment, but those opponents' records are actual, rather than projected.
'but if that were its only drawback, the criticisms wouldn't have much traction (much like those directed toward the wild card'

How is this different than the wild card? Aren't the AL east teams 'forced' to play their 'natural rivals' in the division 18 times, so Tor gets 54 games against NYY/Bos/TB while Tex gets 54 against the A's/Sea/LAAOC. Or to bring it back to the NL Central. For the last couple years Stl/Cin have got to play extra games against Hou/Pit while the Marlins and Mets have got extra games against Atl/Phi. Why no outcry on this? The divisions are no less unbalanced with regard to scheduling than interleague which when you take out the effectively equivalent middle teams boils down to 6 or so games against tougher or weaker competition. 3.7% of the schedule.

And why does the sport with the longest schedule in professional sports always seem to have more whinning about unbalanced scheduling? 162 games would seem to give 'superior' teams a far better chance to separate from their competitors than say 81 or 16? In the NFL the first place teams play two extra games against other 1st place teams, intentionally giving them a harder schedule. This is 12.5% of the schedule. I never hear any complaining about this.

If people don't like interleague I can understand that. Just admit you dont like it because you are a traditionalist. Don't give me bogus arguments that it 'skews' competitive balance. If people were truly concerned about a balanced schedule these same people would push for every team in the league to play approx the same number against everyone. When we all know they don't and you rarely hear anyone complain about that.
Of course the AL East teams have it very different than the AL West or NL Central teams. But the intra-division schedules have little bearing on other divisions because, for example, the A's are vying for the AL East crown. Within their divisions, the schedules are balanced. And, since teams are only fighting their division-mates for the crown, that's all that matters.

The wild card does complicate things in that regard; I hadn't considered that. I'm not sure I've ever heard that as a major criticism of the WC, though (at least not in those words). I'll have to think on it...
To be clear. I hate the wild card for prtty much the same reasons.
Didn't Houston play in Toronto just this past weekend?
Yes, you're right. I made a couple of transcription errors as I typed in each teams' opponents. They have been fixed. The calculations and conclusions are unchanged, though (there were no transcription errors in the math ;-)

Thanks for pointing it out.
I understand your criticism with the strength of schedule, but I would like to point out that a lot of people came out to watch the Reds / Indians series. Yes, the "battle for Ohio" is an artificial way to bring people out to a game, but getting people excited about seeing a good young team is good for baseball.

Is winning percentage the best way to define strength of schedule? The Reds are #1 on your list, but had the fortune of playing the Indians when their two best hitters are on the DL. Also, they were lucky enough to not face the Indian's opening day starter (Carmona) and the team ace (Masterson). St. Louis is #2 on your list because the Royals had a fluke April? Would the Brewers trade a Minnesota series (when the Twins should be more healthy) for a KC series?

How does the trade deadline affect strength of schedule (relative to interleague play)? September callups? Injuries? I am not saying that, since it is impossible to make things fair we shouldn't try to make things more fair, but if natural rivals bring more people to the ballpark, then it might not be so bad.

BTW, I a firm believer that the natural rivalry cost the Reds the 1999 Wild Card.
Those are very fair points. Attendance and excitement is a true plus of interleague and shouldn't be dismissed out of hand.

I'm not against interleague (I'd probably describe myself as ambivalent), but I do think an unbalanced schedule is a very legitimate criticism of it. A 162-game season is, like you said, much more complicated than any stretch of 18-games can ever be. Still, that doesn't mean the unbalanced nature should be ignored.

As for win percentage, I think it's the best tool that we have at the moment (ie, in late-May). Sure, by the end of the season, a player's full stats and a team's full schedule will better tell us just how tough/easy each team had, but that doesn't help us today.
...The Mets, who won that wild-card, had to play the Yankees 6 games that year...
Well said Nater, 162 games is more than enough time to determine who is best.
Agreed. Play the hand you are dealt and win enough games to get in. No whining!
Mistake: the Cardinals don't play @ Boston, but they do play @ Baltimore. I'd say that's just a small difference since Baltimore's lineup is equally as stacked.
Thanks. As I said to mgolden above, there were some transcription errors, but the math didn't change.

Thanks for pointing it out.
I've long that that interleague is a side-show, but does have a place in the game. I would, however, limit it to two series per year. One against a designated natural rival and one random. Two NL clubs would have to forego the random, but it seems to me that 6 series are a bit much.
I think the point of the article in the general sense is true, but I believe the actual numbers are a bit misleading. While some teams may be better than expected, and some worse, I don’t think using teams’ current records are good for this analysis. The two teams whose real-life record differ the most from their BP rest-of-season record are Cleveland (real: .659, ros: .479) and Minnesota (real: .333, ros: .517). Cleveland’s great, and unexpected, record makes Cincinnati’s schedule look tougher than it is, while Minnesota’s poor play makes Milwaukee’s schedule look easier than it is.

I combined the real-life records of each team with their rest-of-season records here at BP and ran those numbers. Those opponents’ winning percentages are:

CHN .524
MIL .522
CIN .518
HOU .516
PIT .502
STL .486

To me, that feels more right than leaving the Cleveland and Minnesota anomalies in there. That being said, I think strength of schedule is extremely hard to figure out with certainty. There are so many variables; who’s on the DL during the series, roster moves, etc. And of course momentum is the next day’s starting pitcher.
I tend to agree with the comments of Nater1177 and ostrowj1. I understand the imbalance of the schedule. I know Joe Sheenan rallied against it as well. I guess I just don't see it as that big of an issue.

For one, all schedules are imbalanced. As Nater1177 pointed out, AL East teams face a much more difficult schedule by virtue of the divison than an AL West team. Yet they both compete for the same wild card.

And sure, the imbalance in the divisions only affects the wild card. It does not affect the internal divsion champ. That's where a few interleague games could make the difference. But as ostrowj1 pointed out, not all games against the same team are equal. Playing Seattle may seem easy since it generally sucks as a team. But if the opposing pitcher is Felix Hernandez, the level of difficulty goes way up. Texas and Oakland may face Seattle the same number of times, but its entirely possible Felix pitches against Texas 5 times and Oakland once in the course of a season. The pitching rotations, line-ups, injuries, and streaks of the various players will all change day to day and week to week. So even playing the same team is not always the same.

Finally, when talking about baseball, were're talking about thin margins between success and failure. Play .400 ball puts you on pace for nearly 100 losses and to be among the worst teams in baseball. Playing .600 ball puts you on pace for 100 wins and possibly being the best team in baseball. Most teams are somewhere in the middle. The difference between Cincinnati's schedule and Milwuakee is expected to be what, 1 game out of 20? It might make a difference, but it's small are hard to quantify. As ostrowj1 pointed out, Cincinnati may have played Cleveland, but did so without some of Cleveland's best players (and also avoiding its # 1 starter)
I'm glad somebody brought up pitching rotations. I beat the drum for the 5-game series being the standard. Not only does it even out the schedule, it allows home team fans to see great starters from other teams when they come through town.
Call me crazy, but this is how I would solve the AL/NL tomfoolery:

Step 1: One team moves from the AL to the NL and goes into the AL West. We'll say the Rockies for the sake of discussion, but the DBacks would work as well. Then the Astros go into the NL West and there are now five teams in every division.

Step 2: I'm fine with keeping interleague, but each team in a division should play the same teams. For example, the NL Central is matched up with the AL East. Each team in the NLC plays one series a piece with every team in the ALE. No more of the 'natural' rivalry nonsense. That's only for when the divisions are matched up or both teams in question make the world series.

Step 3: Use the DH in both leagues. I hate watching the pitcher hit. He usually sucks at it, and when he isn't pitching he should be in the dugout resting and not running the bases. The difference in rules is just silly.

Boom. Problem solved. I'm off! /flies away
hey superhero - you realize of course that an odd number of teams in each league necessitates an inter-league matchup every day of the season?
Correct-one interleague matchup would be going at any given time instead of a set interleague period.
Okay, you're crazy.
I simply cannot believe "scheduling imbalance" articles are still being written when the most obvious divisional imbalance, IN ALL OF NORTH AMERICAN SPORTS, is the fact that each NL Central team has to battle with 5 others, instead of 4 or even 3, for a title.