Who do you think is our biggest competition in the division? I think a pretty solid case could be made for the Rays. They have the second base run differential in the division. They're half a game behind the O's and are tied with the Yankees in the standings, and pythag theory suggests the O's and Yankees have been two games luckier. They're basically the only team in the division, other than the Red Sox, that has good pitching and hitting. The Rays are 6th in the AL in xFIP, 6th in the AL in wOBA and 3rd in the AL in UZR. By comparrison, the second place O's are tied with us for first in the AL in wOBA, but they're 12th in the AL in xFIP. The third place Yankees are 4th in the AL in xFIP and they're 12th in the AL in wOBA.
The Rays get the Tiger next and that's a tough matchup. But I expect to see them in second place in the division in a couple of weeks.