Yankees starting pitcher CC Sabathia hands over the ball to...

Yankees starting pitcher CC Sabathia hands over the ball to manager Aaron Boone during the fifth inning of a game against the Red Sox at Fenway Park in Boston on Saturday. Credit: CJ GUNTHER/EPA-EFE/Shutterstock/CJ GUNTHER/EPA-EFE/Shutterstock

BOSTON — It didn’t seem as if the news surrounding the Yankees’ rotation could get any worse, but it did Sunday morning with the announcement that CC Sabathia was headed to the injured list with right knee inflammation.

Sabathia, who intends to retire at season’s end, allowed five runs and nine hits, including two homers, in 4 1⁄3 innings in Saturday’s 9-5 loss to the Red Sox. It was his second poor start during a seven-game stretch for the Yankees’ starting rotation that was the worst in club history.

Sabathia is 5-6 with a 4.78 ERA in 17 starts this season, including 0-2 with an 8.79 ERA and eight homers allowed  in his previous three outings.

Asked after Saturday’s game about the right knee that already had landed him on the IL in late May — and has consistently given him issues since at least 2013 — Sabathia didn’t use that as an alibi.

But he didn’t directly answer the question of whether it has been giving him more trouble of late.

“No, I’m not going to make excuses,” said Sabathia, who could be headed for a lengthier IL stint this time around. “I’m out there, I’m expected to get outs.”

The rotation collectively has not been doing nearly enough of that of late.

The group, which general manager Brian Cashman is desperately trying to upgrade before Wednesday’s trade deadline, entered Sunday’s game with a 17.67 ERA and 2.74 WHIP in its last 27 innings, allowing 57 runs (53 earned), 61 hits (including 19 homers) and 13 walks.

Tyler Wade was recalled from Triple-A Scranton/Wilkes-Barre. Wade, a solid fielder at multiple positions, hit .204 with a .520 OPS in 20 games with the Yankees this season but performed better in Triple-A, hitting .309 with an .809 OPS in 67 games.

Aaron Boone said Wade was brought up instead of a pitcher because of the uncertainty surrounding DJ LeMahieu, who has been dealing with a groin issue. On Sunday, LeMahieu said he “definitely” could play if called upon, adding that the groin felt significantly better than it did Saturday.

“I don’t feel like if I was in there I would play guarded or anything like that,” he said.

Boone said he would use LeMahieu only in an “emergency” situation Sunday with the hope that after Monday’s off day, he can be an option Tuesday.

“We’re optimistic that we can avoid an IL situation with this, and we’ll just keep evaluating it, obviously, every 24 hours,” Boone said. “But [we] feel good about where he’s at right now.”

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