Maybe this time was the last time.

Maybe this 558th start of the indomitable CC Sabathia’s major league career will prove to be the final one before the 39-year-old lefty calls it a day once the season ends.

Maybe this time the spit and bailing wire holding together a right knee that has been an issue for at least six years — and the cause of multiple trips to the injured list the past three seasons and twice this year — have finally given way for good.

This is the takeaway from Friday night when, following a 1-2-3 third inning that included career strikeouts 3,081 and 3,082, Sabathia left a 1-1 game against the Athletics after having thrown 48 pitches when the pain in that knee reached the level of “10,” according to the pitcher.

“It just got bad again,” Sabathia said after the generally reliable bullpen imploded in the middle innings of what became an 8-2 defeat to the A’s in The Bronx. “It was hurting all night.”

It is premature to declare an end to this pending Hall of Famer’s career even as he announced before the year that this 20th big league season would be his last. That’s why there are qualifiers attached to the situation. Sabathia has pitched through pain before. He wouldn’t be the first athlete to go out on his sword but is in no hurry to join the list. He intends to go through what has become a regular course of treatment that could include another cortisone shot and then give it another go on the mound.

“I hope so,” he said. “Hopefully I’ll get enough rest and it calms down and I’m able to get out there and throw 100 pitches.”

Sabathia has thrown as many as 100 pitches once this season in his 20 starts, 104 in a six-inning no-decision against Toronto on June 24. That followed his first stay on IL this year from May 23 through June 2. He has made three starts since coming off his second stint on IL on Aug. 18, throwing 67, 78 and 48 pitches, respectively.

The plan, though, was to let Sabathia go in this one.

“We’re kind of building it back up,” Aaron Boone said before the game. “He’s probably not stretched out like he would be when he’s really in the flow, but hopefully it gets built up to that point and his body allows him to pitch the way he’s capable.”

Plans, however, sometimes go awry.

And now the plan is to wait and see with four weeks and 26 games remaining in the regular season … four weeks and 26 games remaining in the 20th and final season of Sabathia’s venerated career. Four weeks for Sabathia to get healthy enough to take the mound at least one more time.

“I hope so,” the manager said when asked if he believed Sabathia could continue to defy the pain and make yet another return. “I mean, I don’t want to speculate on that. We’ll see how it goes as far as treatment and then go from there.”

Sabathia likely would be a long shot to make the postseason roster as a fourth/fifth starter even if he could give the team some length.

Masahiro Tanaka and James Paxton are locks to start, Luis Severino is a pretty good bet if he is healthy and there is Domingo German, who sports a 17-3 record with a 4.03 ERA.

The Yankees likely will employ a cast of thousands in a bullpen that might include both Dellin Betances and Jordan Montgomery if the rehabbing pitchers are deemed ready. Know this: Sabathia has never even once pitched in relief throughout his big league career.

Boone’s staff will have to include an innings-eater or two. While Sabathia has a myriad of existential qualities and is venerated as a teammate and now celebrated as a brand, chewing up innings is not among his attributes after having thrown 3,570 ¹/₃ of them throughout his regular-season career and another 129 ¹/₃ in the postseason. He hasn’t gone more than four-and-a-third innings in any of his past five starts.

After 20 years, there may not be enough time for Sabathia to prove himself able, though always willing. How about that.

“I’m not worried about it,” said Sabathia, a driving force in the Yankees’ 2009 World Series victory that stands as the team’s lone title since 2000. “I’ll wait until I’m healthy. Whenever that is, it is.”

You never know, of course. You never can count out a pro athlete with the heart of a lion. But it is possible that a career that commenced with an April 8, 2001 start in Cleveland for the Indians against the Orioles may have reached its end with start No. 558 on Friday.

After so many times, maybe this time was the last time.