PHILADELPHIA — The Washington Nationals have put Max Scherzer on the 10-day injury list because the ace right-hander has a mid-back strain.

An MRI on Scherzer's back came back negative, and the three-time Cy Young Award winner had his start pushed back from Sunday to Tuesday. But he was placed on the injury list retroactive to July 10 after throwing a bullpen session before Saturday's game.

Catcher Spencer Kieboom was recalled from Double-A Harrisburg to take Scherzer's roster spot.

Scherzer was 7-0 with a 0.84 ERA in his last nine starts before the All-Star break. He is 9-5 with a 2.30 ERA overall.