It's a big blow to the Yankees' pitching depth just ahead of the postseason, especially given Cortes' 1.58 ERA over his last 40 innings. He will be eligible for activation Oct. 7 -- which is the day of Game 2 of the ALDS -- but it's certainly possible Cortes will be sidelined much longer than that.

The development ensures Cortes will not be available for the start of the American League Division Series on Oct. 5. The Yankees will turn to Marcus Stroman, who recently shifted to the bullpen, to start in Cortes' place Wednesday.

So much for a total surplus of starting pitching heading into the postseason for the Yankees. Left-hander Nestor Cortes had an MRI on his left elbow on Wednesday, a sudden injury concern for a pitcher that’s been a workhorse for the Yankees all season.

Nestor Cortes was slated to start Wednesday against the Baltimore Orioles as the New York Yankees look to clinch the AL East title with a win. Instead, the left-hander will undergo an MRI on his elbow,