AP Sports Writer
ATLANTA (AP) -- Washington Nationals pitcher Stephen Strasburg may have irritated a nerve in his right arm using an electrical stimulation machine.
The machines are used by athletes to build strength and are attached with adhesive electrodes. Manager Davey Johnson said the device could have been placed too close to a nerve in Strasburg's pitching arm, leading to discomfort in Monday night's start against the Atlanta Braves.
Johnson said the Nationals do not expect Strasburg to have continued problems with the irritated nerve but it was too early to determine whether Strasburg will make his next scheduled start Saturday at Pittsburgh. The manager wants to see how the right-hander throws in a bullpen session.
"I think it will settle down by the time he throws his side," Johnson said. "I think Strasburg feels a lot better about it. So do I."
Strasburg frequently shook his right arm while pitching six innings and allowing two runs in the Nationals' 3-2 loss Monday night.
Johnson said after the game Strasburg "doesn't look right to me." The manager said he was concerned Monday because Strasburg struggled with his control while walking four batters and shook his arm so often between pitches.
"He always does this a little bit, but it was so pronounced yesterday, it really worried me," Johnson said Tuesday. "But he feels all right about it so I feel all right about it."
Asked after the game why he was shaking his arm, Strasburg said "You just try to stay loose."
Strasburg insisted Monday "I'm not missing my next start. I'll tell you that right now."
He had lost a career-worst four straight starts before pitching six innings and getting a no-decision Monday night. He is 1-4 with a 3.13 ERA.
Strasburg struck out the side in the sixth inning, giving him eight strikeouts for the game.
The right-hander was examined by a doctor after the game but the Nationals said he was not given additional tests Tuesday.
"The way he finished off the sixth was pretty impressive, and the doctor didn't think anything was wrong, so that's good," Johnson said.
Washington held out right fielder Jayson Werth on Tuesday, a day after Werth crumpled to the ground when he fouled a ball off his left foot in the eighth inning. He completed his at-bat and was replaced in right field by Roger Bernadina in the bottom half.
Werth said he also struggled with a tight right hamstring on Monday night.
"I'm not too worried about it," he said of his injuries.
Tyler Moore started in left, with Bryce Harper shifting to right.
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