PHOENIX -- D-backs outfielder Justin Upton was placed on the 15-day disabled list prior to Friday night's game against the Dodgers at Chase Field.

Upton has been out since July 9, when he strained his left oblique while taking batting practice in Washington.

The move means Upton is eligible to come off the disabled list July 24, but D-backs manager Bob Melvin is unsure if he will be able to return that soon.

"He just wasn't in a position last night even when we had him in the cage taking some tee swings where he couldn't let it go," Melvin said. "How long it will be I'm not sure."

After getting off to a torrid start, Upton has cooled off, hitting .242 with 11 homers and 31 RBIs.

Veteran first baseman Tony Clark, who was reacquired from the Padres on Thursday, replaces Upton on the 25-man roster.