The Boston Celtics and Marcus Smart have agreed to a four-year contract extension. (AP photo)

Marcus Smart and the Boston Celtics have agreed on a four-year, $77 million contract extension, ESPN reported on Monday.

Smart, 27, averaged 13.1 points, 5.7 assists per game playing 32.9 minutes, all career highs. It wasn’t certain, however, whether new Celtics head of basketball operations Brad Stevens, who coached Smart, would want him back.

Smart has always been seen as an elite defender, but there was plenty of speculation that the Celtics would try to trade him.

His extension, ESPN reported, would take effect in the 2022-23 season, and is the max allowable, ESPN said, based on Smart’s $14.3 million salary for this upcoming season.

Smart has played his entire seven year career with Boston, averaging 10.2 points a game in his career. He was the sixth overall pick in 2014 out of Oklahoma State. Smart confirmed the deal on his Instagram account on Monday.