Sam Hauser missed just five total games for the Celtics over the last two regular seasons. He’s already surpassed that number this season thanks to a nagging lower back issue that’s bothered him since the summer.

Hauser, one of Boston’s top bench options, sat out seven of the team’s first 30 games, including two last week. Five of those absences were because of a back injury. Hauser also missed one game with an adductor strain and another for personal reasons.

“It sucks,” Hauser said at morning shootaround ahead of Friday’s matchup with the Indiana Pacers at TD Garden. “Obviously, getting hurt’s never fun. But I’m just trying to do everything I can not to let it not happen again.”

Hauser’s latest layoff came at an inopportune time, as the sharpshooting wing had begun to find his stroke from 3-point range after an inconsistent start to the season. He was shooting 46.5% from three over his previous seven games, compared to 32.5% over his first 14 appearances.

In his first two games back in the lineup, Hauser attempted just one field goal and scored zero points over 30 minutes. The Celtics were outscored by 17 total points with him on the floor in consecutive losses to Orlando and Philadelphia.

“It’s been a little frustrating,” Hauser said. “Just in and out, playing, not playing. Trying to find a rhythm, and that’s tough sometimes. But just working through it.”

Fellow core reserve Payton Pritchard, the early front-runner for NBA Sixth Man of the Year, also has slumped of late, shooting 4-for-16 from the floor (25.0%) and 1-for-13 from deep (7.7%) over the last two games. The Magic and 76ers each outscored Boston by 12 points during Pritchard’s minutes.

Pritchard is the only Celtics player who has appeared in every game this season.

The Celtics listed guard Jrue Holiday (shoulder) and center Kristaps Porzingis (ankle) as questionable for Friday’s game. Holiday sat out Boston’s Christmas Day loss to the Sixers, and Porzingis exited that game at halftime.