And of course, the Yankees have the all-time best Interleague record, 164-109, a .601 winning percentage. In the 15 seasons of Interleague Play, the Yankees had one losing Interleague season record, and that one was in 1997, Interleague Play's first season. But overall, the Yankees have led the charge as the American League has won every season's Interleague series since 2004.
Why is this true? Why not? In the years after the inception of Interleague Play, the Yankees won three World Series in a row. In the 15 years Interleague Play had been in effect before this season, the Yankees qualified for the postseason 14 times. While they have had relatively little postseason success in recent years, 2009 aside, the Yankees have still been a regular-season powerhouse. Thus, they would be completely capable of defeating most of the competition from either league.
Both the Mets and the Braves had the appearance of being NL East contenders before playing the Yankees. But the Yankees defeated the Mets by a cumulative score of 18-7, and the Braves by a 12-6 total. Most of the games in these two series were close, but what they had in common was the result.
It turns out that, by the numbers, the Yankees' toughest Interleague competition could come this weekend in our nation's capital; three games against the Nationals starting Friday night. In fact, this series will feature teams with two out of the three best records in the Majors. The Yankees lead the AL, while the Nats' record is second in the NL only to the Dodgers.
The Nationals, leaders in the NL East, won their sixth straight game Wednesday night with a 6-2 victory over Toronto. The Nationals win the old-fashioned way, with pitching. They are the only club in the Majors with a team earned run average under 3.00. They have advanced to their current, lofty status despite a series of injuries that had limited their offense. They are merely 12th in the NL in runs scored, but their pitching has been so good that tons of runs have not been necessary.
The Yankees will not have to face the acclaimed ace of the Nationals' rotation, Stephen Strasburg (8-1, 2.45 ERA), who just defeated Toronto on Wednesday. But the strength of the Washington rotation is a matter of both quality and quantity, and the caliber of the starters the Yankees will see in the District of Columbia has been beyond question this season. The scheduled pitchers for Washington for this series, in order, are: Gio Gonzalez (8-2, 2.35), Jordan Zimmermann (3-5, 2.91), and Edwin Jackson (3-3, 3.02).
With the way both clubs are playing, this series has the look not of an Interleague curiosity, but of the best matchup of the Interleague season.
"The Nationals are playing great," Yankees manager Joe Girardi said. "I know they swept Boston, they swept Toronto. They're playing extremely well. And we're playing extremely well."
The Yankees are 16-4 since May 22. If the Nationals were a surprise to many people, the Yankees being in first place is never a particular shock. But one aspect of their current game has been a bit surprising. Despite losing Mariano Rivera for the season, and then his successor, David Robertson, from mid-May until later this week, the Yankees' bullpen has emerged as a rock-solid source of stability.
It's more than the top-shelf job turned in by the current closer, Rafael Soriano, who Wednesday night got his 11th save in 12 save opportunities this season. Girardi spoke of relievers "pitching innings they're not used to pitching" for the Yankees. The intersection of Cody Eppley and the eighth inning Wednesday night was one example. Pitching in a one-run game, with one out, the tying run on third and the potential winning run on first, Eppley got a very tough hitter, Martin Prado, to ground into a double play.
Eppley, 26, was claimed on waivers after being designated for assignment by the Rangers in early April. The Rangers haven't missed on many pitchers lately, but Eppley has responded when the Yankees asked him to play a more prominent role. Girardi, in describing the work of his relievers, suggested that not only were his relievers "stepping up," but he used the term "thriving" when describing the work of the Yankees' bullpen. This did not seem to be any form of exaggeration.
In any case, the Yankees are in fine form as they get ready to meet their biggest Interleague challenge, which the record clearly states is, in fact, the Washington Nationals.