Brooks appeared in 18 games for the Memphis Grizzlies during his sophomore campaign. He played a reserve role, averaging 18.3 minutes per game off the bench. Brooks contributed 7.5 points per contest, hitting over 40 percent of his shots from the field. He displayed his long-range skills by shooting 37.5 percent from three-point range. The small forward also hit over 73 percent of his shots from the foul line. Brooks scored in double figures on five occasions. He posted a season-high 19 points against Boston on Dec. 29. Brooks also chipped in 1.7 rebounds per game during his time on the floor. He grabbed a season-best six boards against Phoenix on Oct. 27. That may have been his best all-around game of the season, as Brooks also added two assists and two steals in a 117-96 win over the Phoenix Suns.

Following three seasons at Oregon, Brooks was selected with the 45th overall pick in the 2017 NBA Draft. He proceeded to play in all 82 games for the Grizzlies, including 74 starts. Across 28.7 minutes per game, he averaged 11.0 points, 3.1 rebounds and 1.6 assists. He also shot 44.0 percent from the field, made 1.1 threes per game at 35.6 percent and made 1.5 free throws per game at 74.7 percent. Arguably, Brooks' best performance of the season occurred during a 137-123 loss to the Thunder. He started, played 33 minutes and posted a career-high 36 points, seven rebounds, two steals and an assist. His other career highs stood at eight rebounds, eight assists, five threes, four steals and two blocks. Brooks racked up seven performances with at least 20 points, 23 with at least five rebounds, two with at least five assists, five with at least three steals and 13 with at least one block. Brooks also made at least three three-pointers on 13 occasions.