CINCINNATI (AP) The Washington Nationals put Stephen Strasburg on the 15-day disabled list on Saturday, a day after he had to leave a start after 16 pitches because of a stiff neck.
Strasburg had a rough May, failing to last four innings in four of his five starts. He left one start with tightness behind his right shoulder.
The left side of his neck tightened after the first inning of a 5-2 loss to the Reds on Friday night, and he came out of the game after facing only one batter in the second inning. Manager Matt Williams said the team wants to find out why he's having back and neck problems.
''We've got to get the bottom of what's going on,'' Williams said. ''It's perplexing because it's not anything you can point to.
''So we'll get this thing worked out and hopefully he'll be back in 15 days.''
Williams hasn't decided who will take his spot in the rotation. Right-hander Taylor Hill was called up from Triple-A Syracuse to shore up the bullpen for a few days as a long reliever. Hill was 3-2 with a 4.35 ERA in nine starts at Triple-A Syracuse.
Strasburg is 3-5 with a 6.55 ERA in 10 starts. The NL East leaders also are missing starter Doug Fister, who went on the disabled list on May 15 with tightness in his forearm. The Nationals also learned this week that outfielder Jayson Werth is out indefinitely with two fractures in his left wrist, which was hit by a pitch.
Strasburg, 26, hurt his left ankle during a conditioning drill in spring training. The Nationals want to figure out whether the problems are caused by Strasburg changing his delivery to compensate for the ankle problem.
Strasburg was on his way back to Washington on Saturday. He's scheduled for exams on Monday.
''Something's causing him discomfort in his upper back,'' Williams said. ''The fact that it switched sides wouldn't point to anything structural. We've got to get it figured out.
''He's never had an issue with his arm. It hasn't been his elbow or his shoulder or anything like that. It's something to do with his back and his alignment. It could be from his ankle (injury) and the adjustment he's made from where he's landing and having to throw across his body more. We've looked at all of that.''
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