The finest coach in NBA history is optimistic about the Boston Celtics’ chances this season.

Following the Boston Celtics’ 33-point thrashing of the San Antonio Spurs on New Year’s Eve, Spurs head coach Gregg Popovich referred to his club as a “championship-caliber team.”

Popovich understands what it takes to win an NBA championship. During his tenure as head coach, the 74-year-old has led the Spurs to five championships, the most recent being in 2014, when San Antonio defeated the Miami Heat in five games in the championship series.

Boston will look to keep its winning ways going when it visits the Paycom Center on Tuesday to face Shai Gilgeous-Alexander and the Oklahoma City Thunder.