Jared Sullinger may not receive as much attention as Avery Bradley’s return has in getting the Celtics going as of late, but the rookie has been vital to the team’s success.

Boston has won a season-high six consecutive games, with Sullinger averaging 9.8 points and 9.3 rebounds on 62 percent shooting from the floor. He has come off the bench in every game since early November, but has seen his minutes become more regular as of late.

Sullinger ranks third among rookies in total rebound percentage (18.14 percent) and also sits in the top-five in both offensive and defensive rating. He grabbed a career-high 16 boards against the Suns on Jan. 9 and has three double-digit efforts in the last six contests.

The former Ohio State star is playing 25 minutes per game this month, up from 17.7 in December. His fouls have increased along with his playing time. He has fouled out three times in his last seven games and has been called for 4.6 fouls per game this month.

“Everybody has to pay their dues,” Sullinger said when asked if referees are harder on him as a rookie. “I’m just trying to get better every day.”

His foul rate has remained level with increased time, which is an encouraging sign. Sullinger was whistled for .186 fouls for minute in December and his rate for January is .184.

“Half of my fouls come because I’m just out of position,” Sullinger explained, “I’m working on that.”

Adjusting to the NBA game takes time. With every minute he logs, Sullinger’s ability to put himself in the right position will increase. The list of post players that have had foul issues early in their careers is a long one. Sullinger isn’t the first and won’t be the last.

Other than working on his footwork and anticipation, there isn’t much Sullinger can do in relation to how referees officiate his play. He can, however, gauge how games will be called in the early going.

“I’ve been managing that lately. Understanding what type of referees we have and if they are going to let us be physical or passive,” he said. “I just try to read the refs and see what type of a game it’s going to be.”

The Celtics are pretty thin in the paint as Fab Melo gets seasoning in Maine and Jason Collins continues to show his age. They may get Chris Wilcox back on Wednesday night, but it should be Collins and not Sullinger who sees a reduction in his minutes.

Danny Ainge took a chance on Sullinger when he fell to the 21st pick over concerns about past back issues. So far that gamble has been one of the main reasons why the Celtics have won six games in a row.