Clayton Kershaw lasted only five innings in his return from the disabled list and will have an MRI on his back Friday.
The Dodgers ace exited Thursday's start, a 2-1 loss to the Phillies, with back tightness and he'll now stay in Los Angeles as his teammates begin a series with the Rockies in Denver.
The Phillies mustered one run and four hits off Kershaw while he threw 42 of his 62 pitches for strikes.
Back injuries have sidelined Kershaw over the past two seasons, including a herniated disk that forced him to go more than two months between starts in 2016. It's also worth noting that the lefthander's fastball was clocked in the high 80s, noticeably lower than the 92.1 mph he's averaged this season.