Nationals' Strasburg exits early with tightness in left side

Washington Nationals right-hander Stephen Strasburg left Saturday's contest with the San Francisco Giants in the fourth inning with tightness in his left side and will be re-evaluated Sunday.

"We will continue to evaluate (his left side) and see how he is tomorrow," manager Matt Williams said after the 9-3 win over the Giants. "Given his season, so far, I don't want to take a chance there."

Strasburg displayed discomfort in his left side, indicating a possible oblique injury, while pitching with two outs in the inning. He was relieved by Tanner Roark.

Strasburg, who's already spent time on the disabled list with a strained left trapezius muscle this season, had allowed one hit and no runs on 56 pitches before exiting. He's also dealt with minor ankle and back issues.

Following the game, he said he tried to talk Williams into letting him stay in the game. Either way, he acknowledged that he was uncomfortable on the mound with the injury.

"Since that was going to be the case, I iced it a couple of times," Strasburg said. "I really don't have an explanation (for the injury). Everything felt good. I threw a pitch to (Buster) Posey. He grounded out and I felt the grab (in my side)."

The 26-year-old fireballer had pitched exceptionally well in his previous two starts since returning from the DL, yielding just two runs and amassing 16 strikeouts over 12 innings.