Tonight is a big game on many levels. A win by the Rays pulls them back to within one-half game of the division lead and would leave the Rays and Yankees tied in the all-important loss column. Also, the American League Cy Young Award could be on the line as two of the favorites, CC Sabathia and David Price will go head-to-head.
But more importantly, if the Rays win tonight, they will clinch the season series with the Yankees (10-8). And in doing so, the Rays would clinch the tie-breaker with the Yankees should the two teams finish the season tied atop the AL East.
If the Yankees win tonight, and the two teams finish tied, the division title will be decided by divsional record. A Rays loss tonight would leave them 40-29 in the division with the Yankees at 36-27. The Rays have three divisional games remaining (vBAL) while all 9 of the Yankees remaining games are intradivisional (3vBOS, 3@TOR, 3@BOS). If the Rays win 2 of 3 versus the Orioles, the Yankees would have to go 7-2 in their final 9 games to win the tie-breaker (the Rays would hold the third-tiebreaker, 2nd-half record).
In other words, in addition to the easier schedule, the Rays are in a strong position with tie-breakers, even with a loss tonight. Therefore, in order to win the division, the Yankees most likely must win it outright, while the Rays need only tie.