Nationals outfielder Jayson Werth didn’t play Sunday because of a lingering cramping hamstring and first baseman Adam LaRoche didn’t start because of a sore back. Both players said they expect to return to play on Monday in the opening game of a four-game series against the Chicago Cubs.

Werth, the Nationals hottest hitter of late, exited Saturday’s game in the ninth inning with cramping in his hamstring. He warmed up and felt fine during sprints before Sunday’s game. But about 40 minutes before first pitch, Werth said it didn’t feel ready. He told Nationals Manager Davey Johnson he could play later in the game if needed.

Bryce Harper played right field in Werth’s place, and Roger Bernadina started in center field and hit leadoff. Bernadina went 0 for 4.

“I’m hoping by tomorrow it’ll be fine,” Werth said.

LaRoche sent Johnson a text message on Saturday night asking him, if possible, to rest his sore back that flared up recently during a stretch of six straight games without an off-day. LaRoche said he could still play, if needed, as well. LaRoche, who pinch hit in the sixth inning on Sunday, dealt with lower back spasms in late July.

“His back has been bothering him the last two, three days but he’s been hitting the heck out of the ball, so I haven’t even asked him how he’s been so when he texted me last night I said you’ve earned it,” Johnson said. “I’ll give you a breather, but he came to me today when he saw Jayson wasn’t in the lineup. He said I’ll give it a go. I said no. [Chad] Tracy needs the at-bats.”

Tracy hit fifth in the order and played first base, finishing 2 for 4 with a run scored.