Pritchard won the award by a very large margin - receiving 82 of 100 first-place votes.
He led the league in points off the bench (1,079) and set a career high with 14.3 points per game. He also set a new career-high in three-point shots made (255), with 246 of them being the most by a reserve player in NBA history.
Pritchard even put up 43 points and 10 rebounds in his best game of the season on March 5th against the Portland Trailblazers.
Boston selected Pritchard with the 26th overall pick in the 2020 NBA Draft and eventually signed him to a four-year, $30 million extension that'll last until the end of the 2027-2028 season.
A Celtics player has now won the award for the second time in the past three years, with Malcolm Brogdon winning the award after the 2022-2023 season, and the fifth in franchise history.