Cardinals' Keynan Middleton: Could require surgery

Middleton (forearm) will undergo an MRI on Friday and could require season-ending surgery on his pitching arm, John Denton of MLB.com reports.

Middleton was evaluated by team doctors Tuesday, and the organization seems to have concern that he's dealing with a significant arm injury. If he does ultimately require surgery, his season would end before it began, as Middleton has been shelved since spring training with what's been termed a right forearm strain. The reliever signed a one-year, $6 million contract with the Cardinals back in February.