Isaiah Thomas was the clear headliner of the Boston Celtics’ offense Wednesday night. But two side acts who have struggled mightily this season also put on a show.

Forward Tyler Zeller and swingman Jonas Jerebko were two bright spots for Boston in their three-point road loss to the Detroit Pistons. Zeller entered the game in the third quarter and immediately made an impact, finishing with 12 points, three rebounds and an assist in just nine and a half minutes of playing time.

Zeller has been on the fringe of head coach Brad Stevens’ rotation all season and had played a total of three minutes in Boston’s previous four contests. The Celtics big man didn’t waste Wednesday’s opportunity, though, hitting 5 of 7 shots in a promising performance.

“It’s tough,” Zeller said after the game, via the Celtics’ Twitter account. “I try to stay in the gym as much as possible and get reps. I got a little rusty but I try to play hard.”

Jerebko was another Celtic who shook off the rust in a big way. The Swedish forward has had a brutal offensive season to date, shooting just 27 percent (4 for 15) from 3-point range entering Wednesday. But Jerebko finally found his stroke against the Pistons, hitting three consecutive deep balls in the fourth quarter to help Boston get back in the game.

“I’m ready when my number is called,” Jerebko said, via the Celtics’ Twitter account. “I was confident in my looks and I knocked them down.”

Boston prides itself on its depth, but Jerebko and Zeller have been virtual nonfactors this season. Wednesday’s developments certainly were a positive sign, however.

“Jonas and Tyler Zeller gave us a huge lift off the bench,” Stevens said in a postgame interview aired on CSN New England. “It was great to see that.”

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Let’s hit a few other notes from Celtics-Pistons:

— Did we mention Thomas was really good in this one?

The 5-foot-9 point guard tied a career high with 38 points on 12 of 20 shooting while also tallying seven assists. The offensive outburst was a welcome sight after Thomas’ rough night Tuesday in which he went just 3 for 15 in a loss to the Cleveland Cavaliers.

Bounce-back nights appear to be a trend for Thomas, who followed up a 3 for 11 clunker in Atlanta with a 30-point effort against the Philadelphia 76ers in late November. That’s indicative of the 26-year-old’s mental toughness, which Stevens praised before the game.

“What separates him is his competitive will.” Stevens said, via the Celtics’ Twitter account. “He has a constant chip on his shoulder in a good way.”

— Jared Sullinger held his own against one of the NBA’s best big men.

Andre Drummond entered Wednesday as the league’s leading rebounder and got his double-double with 16 points and 12 rebounds. Sullinger essentially matched him on the stat sheet, though, tallying 17 points and pulling down 10 boards for his own double-double.

Sullinger has emerged as one of the best rebounders in the league this season — his 20.3 percent rebound rate is tied for seventh-best in the NBA. The Celtics big man faced a tall task in Drummond but proved he can hang with the big boys, as Boston actually outrebounded Detroit 44-36.

— Boston lost on the road on the tail end of a back-to-back for the first time since February of last season. That snapped a streak of 10 consecutive wins in that scenario, which, as it turns out, is pretty darn impressive.

— It appears Marcus Smart indeed is making progress.

The Celtics point guard hasn’t played since Nov. 20 with a left knee injury but now is doing on-court activities in Boston, Stevens told reporters Wednesday, via’s Marc D’Amico.

Stevens added Smart will have a minutes restriction when he comes back, but there’s still no timetable for his return.

Thumbnail photo via Mark L. Baer/USA TODAY Sports Images

Thumbnail photo via Boston Celtics center Tyler Zeller (44), forward David Lee (42) and forward Jae Crowder (99) celebrate against the Atlanta Hawks during the first half at TD Garden.