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The New York Yankees activated one of their trade deadline additions off the injured list Tuesday while losing another to injury. New York activated Harrison Bader prior to their series opener with the Pittsburgh Pirates, the team announced. Also, Frankie Montas was placed on the 15-day injured list with shoulder inflammation. He went for an MRI this past weekend.

Montas told reporters, including ESPN, the injury is similar to the shoulder inflammation that sidelined him (but did not send him to the injured list) while with the Oakland Athletics in July. He received a cortisone shot and hopes to return in time to make a regular season start. Montas can not be activated until Sept. 30, when the Yankees will have six days and seven games left in their season.

In eight starts with the Yankees, Montas owns a 6.35 ERA and 1.54 WHIP. He could not complete four innings after being staked to an early 5-0 lead Friday, then reported discomfort after the game. The Yankees traded for Montas with the idea he would be their No. 2 starter in the postseason behind Gerrit Cole. Now he's not assured a spot on the postseason roster.

As for Bader, he was acquired from the St. Louis Cardinals for lefty Jordan Montgomery at the deadline. Bader was on the injured list at the time of the trade (he has not played since June 26 due to plantar fasciitis), though obviously the Yankees love his center field defense and were willing to wait. Montgomery, meanwhile, has a 2.35 ERA in nine starts with St. Louis.

The Yankees enter Tuesday in first place in the AL East with a 88-58 record. Their magic number to clinch the division is 11 and their magic number to clinch a postseason berth is four.