Interleague Play in Major League Baseball has definitely lost its luster. However, it's probably also here to stay. So as we prepare for this season's first round of American League vs. National League action this weekend let's shine some light on some interleague trends that might benefit the baseball handicapper.

AL on a Run

Looking big-picture, since interleague play began back in 1997 the American League has won the season series 10 times, including the last seven years in a row. Last year the AL posted a 134-118 record against the NL. And that was actually the best performance by the NL since 2004, when the Nationals lost the series by a 126-125 margin. After that the AL won 136, 154, 137, 149 and 137 of the interleague games from 2005-2009. So over the course of the last seven seasons the American Leaguers own a .552 winning percentage against the National League. Which equates to 89 wins over a 162-game schedule.

Why the dominance?

The biggest difference in the games themselves, of course, is the use of the designated hitter in games played at American League ballparks, and having pitchers bat in National League parks. Now, seemingly the National League might hold an advantage in this aspect of the game, because, for one thing, NL pitchers hit regularly, while AL pitchers rarely bat. So National League teams playing in National League parks would have more experienced batters in the nine spot in the lineups. And when playing in American League ballparks, NL teams then insert a real bat if they've got one, in the designated hitter spot. This might not be an advantage, but it shouldn't be a disadvantage. But here's the conundrum; American League pitchers must be relishing the chance to wield their borrowed sticks, because they've held their own compared to their NL counterparts for the last several seasons. 

In the end, though, it appears that the American League's recent success in Interleague Play comes down to something very simple; the AL, from top to bottom over recent seasons, has had better teams than the NL. Not only has the AL won the season interleague series 10 of 14 times, AL teams have won eight of the last 14 World Series. 

The Best Interleague Teams

Last year six of the top seven teams in the interleague standings came from the American League. The Chicago White Sox led the way by going 15-3, and they're now 39-15 vs. National League teams over the last three seasons. The Texas Rangers went 14-4 in Interleague Play last year. The Boston Red Sox went 13-5, and are now 47-25 in interleague play the last four seasons. The New York Yankees went 11-7 last year, as did the Detroit Tigers and Los Angeles Angels. So over the last four seasons the Angels, at 49-23, and the Tigers, at 48-24, have been the top two teams in Interleague Play. And the Minnesota Twins are 45-27 during the last four years.

The New York Mets led the NL last year by going 13-5 in Interleague Play. This gives them a 35-28 record in Interleague Play over the last four seasons. The Colorado Rockies have been the best NL team in Interleague Play over that span, going 37-26. And the St. Louis Cardinals are 31-29. But those are the only three National League teams to own a winning record in Interleague Play over the last four years. 

The Worst

The worst teams in Interleague Play over the course of the last four seasons come almost exclusively from the National League, and there are a few surprises. The World Series champion San Francisco Giants are 27-36 vs. the AL over our four-season sample. The LA Dodgers, who have won a couple of division titles during this time, are just 23-40 in IL play the last four seasons. And the Philadelphia Phillies, who have won the NL East four times in a row, are a head-scratchin' 28-38 in interleague play over that span.

Of course, none of this is happening in a vacuum, and oddsmakers are well aware of the AL's recent dominance in Interleague Play. So bettors should realize they may be giving a bit more on their bets when taking an American League team this interleague betting season.