In most ways, the distinction between the National League and American League has been forever wiped away. The leagues no longer have separate presidents or umpiring crews, and all administrative matters fall under the purview of Major League Baseball’s central office. The introduction of interleague play 10 years ago has further blurred the lines.
Thus, the days of the NL having the bigger pitcher-friendly strike zone and the AL sporting a strike zone that favors the hitters are a thing of the past. “It’s all the same now,” Yankees reliever Kyle Farnsworth said. “The umpires are graded with the QuesTec system, and that’s made all the strike zones uniform. There is no longer that sense that you are playing under National League rules or American League rules. It’s just baseball now.” Farnsworth should know, as he has spent time in both leagues during his eight-year career, pitching in the NL with the Chicago Cubs (1999-2004) and Atlanta Braves (2005) and in the AL with the Detroit Tigers (2005) and Yankees (2006).
Atlanta right-hander Tim Hudson has also gotten a taste of both leagues, pitching for the Oakland Athletics of the AL from 1999-2004 before being traded to the NL prior to the 2005 season. He also sees little difference in the leagues. “The only thing that changes from one game to the next is the umpires’ strike zone,” Hudson said. “Some have a little bigger zone than others, but it doesn’t carry over from one league to the other, it’s just a matter of who the individual umpire is… When you talk to the real veteran guys, they’ll tell you about how different the leagues were. You just don’t see it any more.”
Toronto third baseman Troy Glaus has spent all but one of his nine seasons in the AL, playing with the Angels of Anaheim from 1998-2004, and last season with the Blue Jays. He took a one-year detour to the NL with the Arizona Diamondbacks in 2005, and also found the strike zone to be the same. However, it did not take Glaus long to realize that there was one big difference between the leagues. “The American League is a lot more offensive league, and that’s because of the designated hitter,” Glaus said. “Teams play a power game. They sit back and wait for the three-run home run. The National League is a different style, though. You see more one-run strategies. There’s more stealing, more hit-and-runs.”
The DH stands as the lone distinguishing factor between the leagues, but it remains a significant difference. Since the DH was adopted by the AL for the 1973 season, the offensive balance has swung to the junior circuit. The only season in which NL teams scored more runs per game than AL teams was 1974. Last season, AL teams scored just under five runs a game, while NL teams averaged 4.8. A fifth of a run may not seem like much, but it’s part of the reason why it’s not a surprise that hitters’ statistics historically improve when they move from the NL to the AL, and pitchers’ numbers are better when they move from the AL to the NL.
“Pitching is never easy in the major leagues, but a game can get away from you a lot quicker in the American League,” Hudson said. “It seems like you can cruise along for three or four innings in the American League, and then a team can explode for five runs in a hurry. In the National League, teams peck away more. They get a run one inning then another run an inning or two later.”
Cincinnati Reds right-hander Bronson Arroyo returned to the NL last spring after spending three seasons in the AL with the Boston Red Sox. He also began his career in the NL with the Pittsburgh Pirates from 2000-02. His ERA was 3.29 last season in the NL after being a combined 4.19 in his three seasons with the Red Sox. “In the National League, there are points in the game where you’ll at least get a breather, when the pitcher comes up and a lot of times with the No. 8 hitter up before the pitcher,” Arroyo said. “In the American League, it never seems to end. It feels like every hitter that comes to the plate is dangerous and you never have the chance to catch your breath.”
Let’s take a look at what PECOTA sees for players changing leagues this season who had at least 250 plate appearances or 100 innings pitched in their former league last year:
Batters Moving from AL to NL
Carlos Lee, Astros: Hit .322/.369/.525 with nine homers and 35 RBI in 260 PA for the Rangers after being acquired from the Brewers in a deadline trade.
PECOTA: .293/.356/.523 with 27 homers and 89 RBI in 570 PA.
Batters Moving from NL to AL
Aubrey Huff, Orioles: Hit .250/.341/.478 with eight homers and 28 RBI in 256 PA for the Astros last season after being acquired from the D-Rays.
PECOTA: .272/.335/.443 with 16 homers and 66 RBI in 481 PA.
Pitchers Moving from AL to NL
Freddy Garcia, Phillies: Was 17-9 with a 4.54 ERA in 216 1/3 innings; averaged 8.9 hits, 1.9 walks, and 5.2 strikeouts per for the White Sox last season.
PECOTA: 12-9, 4.56 in 186 1/3 innings, with averages of 9.0 hits, 2.2 walks, and 5.6 strikeouts per nine.
Randy Johnson, D’backs: Was 17-11 with a 5.00 ERA in 205 innings; averaged 8.4 hits, 2.5 walks, and 7.1 strikeouts per nine for the Yankees last season.
PECOTA: 8-5, 3.90 in 116 2/3 innings with averages of 7.7 hits, 2.5 walks, and 7.2 strikeouts per nine.
Ted Lilly, Cubs: Was 15-13 with a 4.31 ERA in 181 2/3 innings; averaged 9.4 hits, 4.1 walks, and 6.6 strikeouts per nine for the Blue Jays last season.
PECOTA: 10-8, 4.39 in 161 innings with averages of 8.1 hits, 3.3 walks, and 6.8 strikeouts per nine.
Rodrigo Lopez, Rockies: Was 9-18 with a 5.90 ERA in 189 innings; averaged 10.1 hits, 2.6 walks, and 5.9 strikeouts per nine innings for the Orioles last season.
PECOTA: 9-9, 4.94 in 156 2/3 innings with averages of 9.1 hits, 2.7 walks, and 5.7 strikeouts per nine innings.
Mark Redman, Braves: Was 11-10 with a 5.71 ERA in 167 innings; averaged 9.8 hits, 3.1 walks, and 3.8 strikeouts per nine for the Royals last season.
PECOTA: 5-9, 5.91 in 118 2/3 innings with averages of 10.4 hits, 3.1 walks, and 4.0 strikeouts per nine.
Kirk Saarloos, Reds: Was 7-7 with a 4.75 ERA in 121 1/3 innings; averaged 10.2 hits, 3.6 walks, and 3.6 strikeouts per nine for the A’s last season.
PECOTA: 4-6, 5.55 in 87 innings with averages of 11.2 hits, 3.2 walks and 4.4 strikeouts per nine innings.
Barry Zito, Giants: Was 16-10 with a 3.83 ERA in 221 innings; averaged 8.2 hits, 3.8 walks, and 5.7 strikeouts per nine for the A’s last season.
PECOTA: 11-9, 4.25 in 174 innings with averages of 8.2 hits, 3.2 walks, and 6.3 strikeouts per nine.
Pitchers Moving from NL to AL
Miguel Batista, Mariners: Was 11-8 with a 4.58 ERA in 206 1/3 innings; averaged 9.4 hits, 3.2 walks, and 4.3 strikeouts per nine for the D’backs last season.
PECOTA: 7-11, 5.53 in 148 innings with averages of 10.5 hits, 3.5 walks, and 4.3 strikeouts per nine.
Ramon Ortiz, Twins: Was 11-16 with a 5.57 ERA in 190 2/3 innings; averaged 10.5 hits, 2.6 walks, and 4.4 strikeouts per nine for the Nats last season.
PECOTA: 6-9, 5.04 in 119 1/3 innings with averages of 10.2 hits, 2.4 walks, and 4.5 strikeouts per nine innings.
Andy Pettitte, Yankees: Was 14-13 with a 4.20 ERA in 214 1/3 innings; averaged 9.8 hits, 2.6 walks, and 6.8 strikeouts per nine for the Astros last season.
PECOTA: 11-8, 4.29 in 171 innings with averages of 9.4 hits, 2.4 walks, and 6.1 strikeouts per nine.
Steve Trachsel, Orioles: Was 15-8 with a 4.97 ERA in 164 2/3 innings; averaged 10.0 hits, 3.7 walks, and 3.9 strikeouts for the Mets last season.
PECOTA: 5-9, 6.17 in 114 1/3 innings with averages of 11.3 hits, 3.9 walks, and 3.8 strikeouts per nine.
Jamey Wright, Rangers: Was 6-10 with a 5.19 ERA in 156 innings; averaged 9.5 hits, 3.2 walks, and 4.1 strikeouts for the Giants last season.
PECOTA: 5-7, 5.55 in 109 innings with averages of 9.8 hits, 3.5 walks, and 4.4 strikeouts per nine.
John Perrotto is a contributor to Baseball Prospectus, and covers Major League Baseball for the Beaver County Times. You can reach John by clicking here.