Kyrie Irving to have ‘minimally invasive’ knee procedure

Kyrie Irving has been sidelined since March 11.Jim Davis

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PORTLAND, Ore. — Celtics point guard Kyrie Irving will undergo a “minimally invasive” procedure to alleviate soreness in his troublesome left knee on Saturday, according to the Celtics. The timetable for his return is not yet known.

On Friday afternoon, coach Brad Stevens said Irving’s return could depend on how the procedure went. The coach was asked if he meant it depended on what was found by doctors, or if it depended on how successful the procedure was.

“All that stuff,” he said. “I’ll talk more about it after they go through it tomorrow.”

Irving has been bothered by what the Celtics have referred to as tendinitis for much of this season. He was expected to need a minor surgery at some point as a maintenance procedure related to the 2015 surgery that was completed to repair a broken kneecap. It is unclear if Saturday’s operation will do that, but it is obvious that it will sideline Irving for an undetermined amount of time.

Irving, who turned 26 on Friday, has missed Boston’s last five games because of the sore left knee, and he did not accompany the team on its current four-game road trip that began Friday night against the Blazers.

Stevens said he spoke to Irving “for a while” on the telephone late Thursday night.

“He’s a competitive guy,” Stevens said. “He doesn’t want to miss a game. But at the end of the day, obviously his health is the most important thing.”

Irving was expected to get a second opinion this week about how best to proceed, and on Thursday Stevens said Irving had “talked to a couple different people” as he and the Celtics tried to gather information. Still, at that time, Stevens did not seem to believe Irving was facing a long-term absence.

Now, the Celtics are being quite measured as they discuss — or decline to discuss — Irving’s eventual return.

“We don’t really know the full extent of it,” point guard Shane Larkin said. “We just hope that whatever it is, he can come back this year and help us in the playoffs.”

Irving is averaging 24.4 points, 5.1 assists and 3.8 rebounds this season, his first in Boston. The Celtics have essentially locked up the No. 2 seed in the Eastern Conference playoffs, so Irving’s absence in the short term will have no real effect on their upcoming postseason matchup.

Still, there are just 10 games left in the regular season, so it is clear that when or if Irving returns, he will not have much time to regain his rhythm.

“It’s been such a unique year that I think we’ve had so many curveballs that these guys have done a good job just hitting them and playing to their strengths and doing the best that they can,” Stevens said. “I’m really excited about this group on the court this trip.”

The Celtics, of course, are already considerably undermanned.

All-Star forward Gordon Hayward suffered a gruesome ankle injury just minutes into the Oct. 17 season opener, and is almost certainly out for the season. Backup center Daniel Theis is out for the season with a torn meniscus, and Marcus Smart is expected to miss at least the rest of the regular season as he recovers from right thumb surgery. The only positive news is that forward Jaylen Brown has progressed through the league’s concussion protocol and could return against the Kings on Sunday after missing more than two weeks.

“Honestly, I think it’s important to gain a rhythm,” forward Al Horford said. “It’s tough, but it’s important to gain a rhythm. We’ve only been playing together this year, so we don’t have the luxury of the Warriors or a team that’s been together for a while, and those guys can just be good. For us, the more games we can get together with what we have, the better it will be for us.”

The Celtics could be in position to add a player. A league rule stipulates that if three players miss three games in a row, and league officials determine that a fourth player is expected to miss at least two more weeks, a team can add a player via a hardship waiver. With Hayward and Theis out for the year, Smart out indefinitely, and now Irving facing an undetermined amount of time before his return, Boston should qualify.

There are not many great options on the open market, of course. The Celtics could look to sign a player who recently completed his season in the Chinese Basketball Association, but would more likely look at options in the G-League.

“We need Kyrie to be playing at the best possible way he can at the highest level and we just hope that he gets back quickly,” Horford said. “But we don’t know how these things can do. In the meantime, for our group, we need to just focus on what we have and try to do our best without him.”