PHILADELPHIA — At a time when the Yankees are supposed to be adding, they were hit with another significant subtraction on Sunday, one they can hardly afford.

Cody Bellinger was placed on the 10-day injured list with a left hamstring strain that he suffered legging out a double in Saturday night’s win over the Phillies. The All-Star left fielder joins Aaron Judge and Giancarlo Stanton on the IL, as the Yankees were already scuffing offensively while missing those big bats.

It remains to be seen how long Bellinger will need on the IL, but his absence – along with uncertain timelines for returns from Judge and Stanton — only emphasizes the need for the Yankees to add some offense before next Monday’s trade deadline.

Spencer Jones was called up from Triple-A Scranton/Wilkes-Barre to take Bellinger’s roster spot, though Max Schuemann is expected to start in left field for him Sunday night against Phillies lefty Cristopher Sánchez.

“Obviously he’s a huge member of our team and what we do and just a tremendous all-around player,” manager Aaron Boone said Saturday night. “Hopefully, whether it’s some time or not, it’s on the minor side, but we’ll see.”

Bellinger had gone through an extended slump from late June to just before the All-Star break, though he had begun to turn the corner of late: batting .372 with a .903 OPS over his last 12 games. He still has not hit a home run since June 17, but his bounce back was vital for a team scrapping for any kind of production from its lineup.

Beyond the offense, Bellinger has been the best defensive left fielder in the majors this season with 19 Defensive Runs Saved, which trailed only Red Sox right fielder Wilyer Abreu for the most in baseball.