KISSIMMEE, Fla. – The 76ers have been raving over Matisse Thybulle’s defense.

Coach Brett Brown has even said the rookie defensive standout will play a major role and get major minutes against the Boston Celtics in the first round of the playoffs.

So does that mean Thybulle will be in the starting lineup for Game 1 of the best-of-seven series Monday night at The Field House?

“We’re talking a lot about doing different things. It is being considered,” Brown said before Sunday’s practice.

If so, point guard Shake Milton or power forward Al Horford are the starters whom the rookie can replace. The Sixers are keying on Horford, Thybulle, Josh Richardson, and Joel Embiid to provide solid defense against the Celtics’ balance scoring attack. So Richardson, the starting shooting guard, would assume the point guard duties if Milton is the odd man out.

“You know, obviously, I’m not going to tell you that,” Brown said of whom Thybulle could possibly replace. “You know we are talking about a lot of things. But I feel like to your original point, Matisse will have a significant role defensively in this series.”

Thybulle started one of the eight seeding games; 14 of his 65 appearances were starts. His start in the bubble came against the Phoenix Suns when Brown was resting his core starters.

Including the Suns games, the Sixers have a 9-5 record with the defensive stopper in the starting lineup.

The 23-year-old had 14 steals and seven blocks in his seeding games. He finished the regular season with 93 steals and 47 blocks, becoming the eighth rookie in the last 20 seasons to accomplish that feat. Thybulle did it in 1,287 minutes of action. None of the other seven played fewer than 2,000.

Glenn Robinson III out with oblique muscle strain

The 76ers acquired Glenn Robinson III expecting him to provide much-needed depth in the playoffs.

That’s unlikely to happen.

The Sixers announced Sunday that Robinson is sidelined with an oblique muscle strain and and will be re-evaluated to seven to 10 days. Robinson had been dealing with a left hip pointer that had sidelined him most of his time in the NBA bubble. The Sixers received him and Alec Burks in exchange for second-round picks from the Golden State Warriors in February.

Game 1 of the Sixers’ first-round playoff series against the Boston Celtics is set for 6:30 p.m. Monday at The Field House. If he’s cleared in seven days, Robinson could be available for next Sunday’s Game 4.

The Sixers are also without two-time All-Star Ben Simmons, their best defender.

With Simmons’ absence, the Sixers don’t match up well against the Celtics defensively. Richardson and Thybulle are legitimate perimeter defenders. The hope was that Robinson would be able to contribute off the bench.

“The Ben demise and the Glenn Robinson lack of availability is punishing,” Brown said.

The 26-year-old played in only two of the Sixers’ eight seeding games. He also sat out the Sixers’ final scrimmage with the hip injury.

Robinson suffered the hip pointer during a scrimmage loss to the Oklahoma City Thunder on July 26 after landing on his back.

The swingman averaged 7.7 points and 3.1 rebounds in 14 games, including four starts as a Sixer. Robinson becomes a free agent at season’s end.

He was having a career season with the Warriors before the trade, averaging 12.9 points and 4.7 rebounds.