The left side of Strasburg's neck tightened after the first inning of the Nationals' 5-2 loss to the
Manager Matt Williams said he hasn't decided who will take Strasburg's spot in the rotation.
Strasburg is 3-5 with a 6.55 earned-run average in 10 starts. He injured his left ankle during a conditioning drill in
"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."
Outfielder Bryce Harper was scratched from Washington's lineup because of a sore back.
Harper was hit in the middle of the back by a pitch from Cincinnati's
Harper is batting .369 with 13 home runs and 28 runs batted in this month.
Miami Marlins shortstop Adeiny Hechavarria didn't play against the
Hechavarria banged into left fielder Christian Yelich while they were pursuing
Hechavarria is hitting .300 with two home runs and 20 RBIs.
Colorado Rockies left-hander Jorge De La Rosa was scratched from his scheduled start Saturday against the Philadelphia Phillies because of a cut on the middle finger of his pitching hand.
De La Rosa (1-2, 6.51 ERA) is scheduled to start Tuesday's home game against the Dodgers.
Milwaukee Brewers reliever Will Smith will have a hearing Monday for his appeal of an eight-game suspension after being found with a foreign substance on his arm while pitching.
Manager Craig Counsell said that he wasn't sure how soon the team would know the outcome of the appeal.
Smith was ejected from Milwaukee's 10-1 loss in Atlanta on May 21 after Manager