He missed his first 11 shots. With a minute remaining, he still hadn’t scored.

But Celtics rookie Marcus Smart wasn’t worried. When it mattered most, the sixth overall draft pick last June came through in his Maine Red Claws debut Thursday night.

In the final 55 seconds, Smart made a tiebreaking layup after a steal, fed Dwight Powell for another layup that put the Red Claws up for good, then clinched a 110-106 victory by making 4 of 6 free throws as Maine rallied past the Fort Wayne Mad Ants before a crowd of 1,596 at the Portland Expo.

“I know I’m a good free-throw shooter,” Smart said. “When I got there, I was a little nervous at first because obviously my shot was off. Once I hit that first one, I knew I was going to make the rest.”

Smart, who had not played since early November because of an injury to his left ankle and only learned of his assignment to Maine late Thursday morning, was one of the three Celtics rookies in the Red Claws’ lineup. Powell and James Young were the others.

Young poured in 31 points on torrid outside shooting (7 of 10 from 3-point land) and Powell took charge with 11 of his 21 points in the final five minutes as the Claws overcame an eight-point deficit at the start of the fourth quarter.

“I’m just shooting the ball with confidence,” said Young, who had 28 points through three quarters causing Fort Wayne Coach Conner Henry to mutter “He’s killing us” on the sideline. “The team was giving me some great open shots. They passed the ball really well.”

Young also grabbed nine rebounds, tied for the team high with fellow guard Tim Frazier, and played 37 minutes, more than anyone else on either team.

Powell was forced to sit a significant chunk of the second half after picking up his fifth foul with two minutes remaining in the third quarter. He didn’t return until under six minutes left in the fourth.

“I was definitely looking for some opportunities to help the team,” said Powell, who also played for the Red Claws in their 81-80 victory at Fort Wayne in the second game of the season. “I was trying to be aggressive.”

Powell said he liked the atmosphere at the Expo, where he could tell the fans “seemed very engaged. It’s a small arena so you can hear what people are saying. They were definitely locked in to the game. It’s always fun to have intelligent crowds.”

The Red Claws trailed 60-57 at the half as Young scored 23 points – Maine’s only player in double figures.

Fort Wayne, which sports three NBA players of its own (John Jenkins and Adreian Payne from Atlanta and Glen Rice Jr. from Washington), extended the margin to 10 points in the final seconds of the third quarter. Jermaine Taylor and Frazier then hit free throws to make it 87-79 entering the fourth.

Payne, Andre Emmett and Dahntay Jones each scored 18 for the Mad Ants, who got 17 each from Jenkins and Rice.

In addition to Young’s 31 points, he twice set up Taylor for alley-oop dunks, the second of which tied the score at 93 to cap a 14-6 run to open the fourth quarter.

“The biggest thing we have to learn is not to turn the ball over,” Maine Coach Scott Morrison said.

“We had one turnover in the fourth quarter (after 15 through three). That was a big reason we were able to come back and win the ballgame.”

The Red Claws return to action Saturday night at the Expo against Sioux Falls.