WASHINGTON -- Nationals right-hander Stephen Strasburg left Sunday's game against the Marlins after four innings because of back tightness and was replaced by right-hander Doug Fister in a 7-4 victory.
Strasburg allowed four runs on seven hits. In the first inning, he allowed a three-run homer to Justin Bour, and a solo shot to Derek Dietrich three innings later. The Nationals noticed that Strasburg's velocity on his fastball was down, so they decided he was done for the day.
"He had some discomfort in his upper back, so it was a little bit of a recurrence of earlier in the year.