Twice an interim coach himself, Cavaliers’ J.B. Bickerstaff understands the pressure on Celtics’ Joe Mazzulla

Now coaching the Cleveland Cavaliers, J.B. Bickerstaff knows what's it's like to be thrown into the top job unexpectedly.Ron Schwane/Associated Press

In 2015, Cavaliers coach J.B. Bickerstaff was named interim coach of the Rockets after former Celtics great Kevin McHale was fired. Two years later, Bickerstaff became the interim coach of the Grizzlies when David Fizdale was fired.

Bickerstaff was an assistant coach for both teams prior to being elevated to the top post, so he was familiar with the players and their systems. Still, he said, it was a considerable and sudden adjustment. So Bickerstaff has some idea what the past month has been like for Joe Mazzulla, who was named the Celtics’ interim coach following the one-year suspension of coach Ime Udoka.

“It’s hard,” Bickerstaff said. “The job he’s been asked to do is extremely difficult. Obviously he’s got a lot of talent that can help support him. From the outside looking in, it looks like he’s got a bunch of great dudes that want to be successful and go out and win. So that takes some of the pressure off of him. But until you sit in that seat, I don’t care who you are, you don’t know what it’s like to sit in that seat.

“There’s pressures that you face, and a lot of those pressures are internal. Like, he has a team that was in the finals and wanting to get that team back to that same spot and even further. So a lot of times you put pressure on yourself to do those things. So I think managing that pressure and managing the outside expectations can be difficult.”

When Bickerstaff took the reins in Houston, the Rockets were coming off of an appearance in the Western Conference finals. The Celtics, of course, remain the favorites to win the NBA championship this year. Bickerstaff said that being around so many familiar faces should help Mazzulla.

“It’s understanding those pressures you put on yourself,” Bickerstaff said. “But trusting those people that are around you and not trying to put that pressure solely on yourself. And that’s not easy to do. But strong organization, strong support group, great assistant coaches can kind of help navigate that as well.”

Grant Williams reacts after being ejected on Monday. He served a one-game suspension on Friday.Michael Reaves/Getty

Williams serving suspension

Celtics forward Grant Williams missed Friday’s 132-123 overtime loss to Cleveland because he was serving his one-game suspension for making contact with a referee during Boston’s loss to the Bulls on Monday.

After being called for a blocking foul early in the fourth quarter, Williams sprung to his feet and ran toward the bench, and his hip collided with referee Cheryl Flores.

“We’re competitors in the realm that we’re in,” Mazzulla said. “I think it’s finding a balance. Our biggest strengths can be our weaknesses at times. As we grow as people, we learn how to do that. I trust Grant in any and every situation, and that’s it. We talked about that. We’ll all be better.”

Garland misses 4th straight game

Cavaliers All-Star guard Darius Garland on Friday missed his fourth consecutive game due to an eyelid laceration he suffered in his team’s season-opening loss to the Raptors.