MRI shows flexor strain for Nationals' Stephen Strasburg

An MRI has revealed a flexor mass strain in Washington Nationals pitcher Stephen Strasburg's right arm.

What It Means:

Strasburg's ulnar collateral ligament is fine, which is the good news. However, the bad news is that this likely rules him out for the regular season and possibly the postseason as well. As of now, the Nats aren't setting a timetable on Strasburg, since they're waiting for the swelling to reduce before coming up with a rehab plan. The team had been playing around with the idea of using Joe Ross (shoulder) as a reliever when he returns, but they might scrap that idea with a potential opening in the rotation. The Nats could also choose to go with rookies Reynaldo Lopez or Lucas Giolito to take Strasburg's spot in the rotation.

Strasburg owns a 3.60 ERA in 147 2/3 innings this season. His 3.23 xFIP and 30.6 strikeout percentage both rank third-best among qualified pitchers.