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January is absolutely flying by, and we’re rapidly approaching draft season. If you don’t already have your leagues locked down, you’ll be doing so shortly. Tout Wars and LABR both set their league rosters this past week—of note to BP readers, I’ll be leaving Tout Wars NL and moving back to Mixed due to the Astros-related roster contraction while Jason Collette will be moving from LABR AL to Mixed, where he’ll team up with Paul Sporer. This expert league movement reminded me of a request I received from reader Robotey back in August that I was waiting until the preseason to address:

@Derek — I don't know if this under your purview, but as Fantasy devotees go I am strongly of the school that deep 'only' leagues are the only ones worth considering–precisely because they can lead to these tests of attrition that I am currently undergoing. Any chance you may feel similarly may write a passion piece about the test of humanity that is the 'deeper league'?

While I won’t go as far as to say that “deep 'only' leagues are the only ones worth considering,” I do vastly prefer “only” leagues to mixed leagues. So, for those of you still debating what kind of league (or leagues) to play in for the 2013 fantasy baseball season, here is my attempt at persuading you to give an AL- or NL-only league a shot.

While mixed leagues have the built-in fun factor of getting to own multiple superstars, I find it much more gratifying to draft the lesser-known players who outperform their market-based expectations. Mixed leagues often become a game of stars and scrubs, ultimately being decided by whomever’s stars stay healthy and whoever’s scrubs break out. They disproportionately shift in the direction of whoever manages to make the best April pickups. In the first month of the season, tons of players outperform expectations due to nothing more than small sample sizes and luck, and often you’re merely rolling the dice on one or two of these guys in the hopes that you manage to get the one who proves to be legitimate. Whoever lucks into Jose Bautista has a huge advantage. Yes, whoever drafts Bautista in an AL-only league has an advantage as well, but in a deep league, nearly every player of note gets nominated on auction day. You’re put to a decision on every player on day one. This adds an element of skill that is absent in the piñata-candy-snatching frenzy that is a mixed-league April.

AL- and NL-only leagues force you to play close attention to everybody. In a mixed league, Cleveland’s backup catcher can safely be ignored, but in an AL-only league, Lou Marson has value. In a deep league, you’re not just caring about prospects like Mike Trout and Bryce Harper; when the Twins recall Brian Dozier to play every day at shortstop, you have to be all over it. It’s easy to say that Adrian Beltre is good; it’s much harder to put a price tag on Kyle Seager. Playing time situations have to be watched closely. A big chunk of guys on mixed-league rosters are locked into playing time, but in deep leagues, you have to decide what to do with a floundering James Loney; is he going to pick himself back up, is he going to be benched, is he going to be traded? Don’t think you’re just going to drop him; yeah, he’s James Loney, but that’s still better than Brooks Conrad.

AL- and NL-only leagues also open up new avenues for strategic thinking. How do you want to structure your roster? If you’re not careful, you’ll end up with holes (or worse, Wilson Valdez) in your starting lineup… unless you’re okay with that and decide to make up for it elsewhere. Would you rather draft a so-so asset who will contribute immediately or gamble on a prospect that might not make it to the majors until July? How do you want to spend your FAAB? Does this decision play into how you structure your roster and spend your money on draft day? Do you want to spend here and there on the Doziers of the world or save up in the hopes that Zack Greinke gets traded over to the American League? In mixed leagues, FAAB bidding is far less exciting and even less challenging. The only guys worth going after are guys in the midst of a potential breakout, newly anointed closers, and the few top prospects that are recalled into regular playing time that aren’t already owned.

Of course, this is all mere opinion—there’s no right or wrong answer here—and there are certainly drawbacks to AL-/NL-only leagues; if one of your big-ticket items gets injured, that might be all it takes to cost you the league since solid replacements are so hard to come by. For me, however, I far prefer the challenges and the ultimate gratification of deep leagues. Where do you guys stand?

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I find that mixed leagues with 20 or more teams provide many of the same challenges. I do agree with the basic idea though and am considering moving away from the smaller (12 team) mixed leagues altogether.
I've played NL-only for 25 years and mixed for only five. I prefer an AL/NL only league for all the reason stated above, plus being in a NL-only league helps me better focus on the players on the teams in the NL who compete against my favorite team, the Cardinals. However, a couple of guys in our NL-only league whine that it's too difficult, that there too many players to keep track of. Before last season, we shrunk the rosters, deleting an OF and C position, and creating an extra UTIL position. This off-season, one owner left, and the Astros left, creating a league of eight owners with a player field of 375.

But, also being in a mixed 5x5 league of 10 owners (OBP instead of BA), gives me a chance to keep track of players in the AL, like Trout, Cabrera, and Pujols.
Obviously the more casual a fan you are the more you'll prefer a mixed league. Not everyone wants to have to know who is third in line for saves on Cleveland, or who Houston's backup C is.

We have NL and AL-only leagues with 40-man rosters, 5-12 keepers, and it's a blast. But it's a lot of work, and only four of the eight of us really put in the time to have a chance to win. I imagine that's typical of many leagues regardless of structure, but that's one point in favor of less rigorous leagues.

We have openings, BTW. Draft at Mohegan Sun, last weekend in March. New guys get $320 instead of 260 to compensate for no keepers.
Weekend before easter - 23/24
Dear Mike W.,

I am interested in your participating in your league could you email me more details about the openings league fees etc... (if you are still looking for owners)... I live in CT so getting to Mohegan that weekend is no problem....

Let me know,

---Jeff W---

email :
I am in a 16 team mixed keeper lg and auction-base draft, with 25 roster spots; and a 20 teams mixed keeper lg with incentive-base draft order, with 35 roster spot (including 4 minor league spots). I 've participated in redraft yearly mixed lg and won 16 teams and 14 teams but choked on 10 teams league. I definitely feel what Mr Carty meant.

While myself being waiver wire shark and FAAB auction manic, draft is my weakness. The blind side of stats (or my usage of stats) led my trapped with the star due for rebound or expected raising value that never actualized. Even with mental notes of not over valuing prospects, I still tie myself with Jake McGee/Matt Moore in the past couple years.

Still, pick scrubs that stood out when your season is in rear mirror is something you can brag about in your annual fantasy league luncheon. And I enjoy picking and trading prospects for big leaguers a lot. With out -only lg, and try to find 14 or 16 reasonable men that doesn't cause saga can even be a hassle that BP may never have an article about. C'est la vie, I guess.

That's why I stick with keeper league. Seldomly a team GM can pull yearly fluke and not make you learn something from him. You want to keep Josh Hamilton for reasonable contract? Sign him to a multi years like Angels and take on the consequence later year (whether it's performance drop, or not). If your time investment not pay out for this season, in a keeper league you may collect your rewards in a couple years. It's a continuously improvement process, not one off luck or not season.

I certainly hope for analysis from BP writers for deep keeper leagues, but also realize there is a smaller market for it. At least I appreciate how expert values the gratifying effect of picking up less known player to outperform just like I do.

I have one disagreement. Leagues where players are lost/FAABed when traded from the NL to AL or vice versa are ridiculous. Why introduce something with that much luck in it.
I play in an AL-only league w/ten teams. We are allowed to keep 2 NLers from season to season. If a guy is traded from league to league mid-season, he stays on your roster and becomes an off-season decision. Those holdover NLers are tradeable between seasons as long as they haven't fallen off one of your league teams' rosters and the team gaining him in trade has room for an NLer. Once your league team drops the NLer, he can't be part of your league unless he moves back to the AL.
It sucks, but it's no more or less a matter of luck than a player getting injured.
I've played in NL only and mixed. I think the argument made in favor of NL/AL versus mixed can be addressed by the number of teams, roster size and format (re-draft, keeper, dynasty). I'm in a 16 team mixed dynasty, with 25 active and 25 reserve slots, plus 8 injured spots in season. You have to know every player and prospect on every team to have success. The more teams and/or roster spots there are, the more you have to know.
Yup. I'm in a deep mixed league -- 15 teams, 22 active roster spots, 5 bench, unlimited DL and 12-player minor leagues (where you don't have to activate them as soon as they get to majors). League is basically a hybrid of keeper/dynasty and gets all benefits of AL/NL-only in terms of depth, w/o the ridiculousness of how to deal with mid-season trades fom one league to another.
I like 14-team mixed dynasty with 40 man rosters the best. I've tried only leagues, but losing players with they are traded out of the league is too much.
How does anybody have time to play a mixed league? In an AL/NL only, you only have to be an expert on one league. I don't play roto type baseball, but I guess the answer is that mixed leagues do not go as deeply. However, that depends on how many managers there are, no? So, if you have the time to be an expert on both leagues, then a deep mixed league would have more managers to trade with.
What's really interesting is how many variations there are in leagues, just among the small group of leagues referred to in this thread. Given that,it makes the concept of dollar values and ADP very hard to pin down.
I'm in 2 (or three, depending on how you define the second) money keeper leagues. Both are auction leagues with traditional 23 man rosters. The mixed league, which has been in existence over 20 years, contains 18 teams. Along with the 23 man roster compiled through the auction and keepers, there is an up-to 17 man reserve roster, which contains anyone, major leaguers, minor leaguers, Japanese players, college players, anyone - I drafted Justin Upton when he was in high school. You keep non-major leaguers as $5 reserves until they use up their rookie eligibility in the majors. This all works pretty great. Just deep enough so we draft guys who play, as well as having people available to be picked up. The reserve draft order is based on where you finished the previous season, giving people a reason to keep paying attention. It also enables draft choices to be used in trades.
My other league is unique. Only nine owners, but each of us has an AL and an NL team. Top three in each league get paid, along with the top two combined. Only ten reserves, make the decisions there tougher and FAAB bidding exciting. If a player is traded out of a league, you keep him in the league he started in, then you can keep him in the other league the next season.
I guess there are those who find the decision over which guys getting 200 AB can be useful as an important part of fantasy baseball. I freely admit that I don't. I like having a budget to allocate in an auction and having some useful reserves to replace injured players - and there are more and more DL stints every season. Given that both of my leagues date back to the last century with remarkable stability, what we do seems to be working.
I concur. I've played in a variety of leagues. My favorite was an AL-only with rules somewhat similar to those used in rotisserie laid out by Okrent and company (namely the 25 man roster filled out at auction and the 15 player reserve roster drafted afterwards).