Celtics ink Robert Williams III to a 4-year, $54 million extension

The Boston Celtics and Robert Williams III have agreed to a 4-year, $54 million contract extension, according to ESPN’s Adrian Wojnarowski.

Williams is coming off an encouraging third season in which he appeared in one more game than he had in his first two seasons combined. He cut down on his fouls and earned the starting center job at the deadline, showcasing athleticism at both ends of the floor and underrated passing chops.

He was tied for sixth in blocks per game during the regular season (1.8) despite playing fewer than 20 minutes a night while also chipping in 8.0 points, 6.9 rebounds, and 1.8 assists per game.

Come the postseason, he impressed in Game 1 of Boston’s first-round matchup against the Nets, recording 11 points, nine rebounds, and nine blocked shots — a single-game Celtics playoff record — in less than 23 minutes of action. Unfortunately, the ankle injury that forced him out of Boston’s play-in victory over Washington flared up and limited him to just six minutes in Game 3 and kept him on the bench for Games 4 and 5.

This deal locks Williams alongside a core of Jayson Tatum, Jaylen Brown, and the recently extended Marcus Smart in Boston for the foreseeable future while making the 23-year-old one of the 15 highest-paid centers in the NBA.

On a per-36 minute basis, Williams averaged 15.2 points, 13.1 rebounds, 3.4 assists, 3.3 blocks, and 1.6 steals last season. If he can continue to build his health — a big “if” considering he still missed 20 regular-season games amid the increased availability — and his defensive discipline, the future of Boston’s center position could get significantly brighter.