Tillman (16-5) controlled the Yanks on two runs, allowing four hits without a walk to become the first O's pitcher since Mike Mussina in 1999 to notch a 16th victory.
Tommy Hunter tossed scoreless eighth inning and Jim Johnson closed out the win with his 43rd save as Baltimore took the first of a four-game series against division rival and fellow American League wild card contender New York.
CC Sabathia (13-12) was reached for four runs (three earned) on seven hits in a 7 1/3-inning effort for the Yankees, who fell three games off the wild card pace.
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