After the conclusion of the 2015–16 season, Brooks said he would remain with Oregon for a third season.[6] He suffered a foot injury in the summer of 2016 and did not play in Oregon's offseason trip to Spain.[5] On November 7, 2016, Brooks was named to the Associated Press' preseason All-America team.[7] During his three seasons of college career Brooks averaged 14.8 points, 4.5 rebounds and 2.6 assists in 28.9 minutes per game.[8]
Brooks was drafted by the Houston Rockets with the 45th pick in the 2017 NBA draft and then was immediately traded to the Memphis Grizzlies.[10] On July 21, 2017, the Grizzlies signed Brooks to his rookie scale contract.[11] On October 18, 2017, during the Grizzlies' season opener, Brooks scored 19 points, the most points scored by a Canadian-born player in an NBA debut.[12]
On April 11, 2018, Brooks scored 36 points along with seven rebounds, one assist, and two steals in a 137–123 loss against the Oklahoma City Thunder.[13] In December 2018, Brooks was thought to be involved in a failed three-way trade between Memphis, the Washington Wizards and the Phoenix Suns; the trade faltered over confusion between Brooks and his similarly named teammate, MarShon Brooks,[14] as the Memphis front office did not intend to trade Dillon while the other teams expected him and not MarShon.
On January 5, 2019, Brooks suffered from a ruptured ligament in his right big toe[15] and underwent a successful surgery to repair it on January 11, 2019. Brooks missed the remainder of the 2018–19 season.[16]
Brooks began the 2019–20 season as the Grizzlies' starting shooting guard. After averaging 16.1 points per game over the first half of the season, on February 5, 2020, he signed a three-year, $35 million extension with the Grizzlies.[17]
On February 28, 2020, Brooks scored a season-high 32 points, along with getting two rebounds, one assist and one block in a 104–101 loss against the Sacramento Kings.[18]
On May 23, 2021, Brooks made his NBA playoff debut, scoring a season-high 31 points, along with seven rebounds, to help the Grizzlies to a 112–109 Game 1 victory over the top-seeded Utah Jazz.[19] The Grizzlies would go on to get eliminated and lose the series in five games.[20]
On October 12, 2021, it was announced that Brooks would miss two to three weeks due to a fracture in his left hand.[21] On December 19, he scored a career high 37 points in a 105–100 loss to the Portland Trail Blazers.[22] On January 8, 2022, during a 123–108 win over the Los Angeles Clippers, Brooks suffered a left ankle injury. The next day, he was ruled out for 3-to-5 weeks with injury, which was diagnosed as an ankle sprain.[23] On April 16, during Game 1 of the first round of the playoffs, Brooks scored 24 points in a 117–130 loss to the Minnesota Timberwolves.[24]
In Game 2 of the 2022 Western Conference semifinals against the Golden State Warriors, Brooks was assessed a flagrant 2 and ejected after he chased down the Warriors' Gary Payton II and hit him in the head when he was in the air, going up for a fast-break layup; Payton fell hard and fractured his left elbow.[25] Brooks was suspended for Game 3 of the series.[26] The Grizzlies would go on to lose the series in six games.
On December 17, 2022, Brooks scored a team-leading 32 points during a 115–109 loss to the Oklahoma City Thunder.[27] On February 2, 2023, Brooks was assessed a flagrant 2 foul and ejected for punching Cleveland Cavaliers player Donovan Mitchell in the groin.[28] The next day, the NBA suspended Brooks for one game without pay for his actions.[29] On March 4, he was suspended for one game without pay for incurring his 16th technical foul of the season.[30][non-primary source needed] On March 17, Brooks was fined $35,000 by the NBA after he shoved a cameraman to the floor during a game two days earlier against the Miami Heat.[31] On March 21, he was suspended for one game without pay for receiving two more technical fouls, pushing his total to 18 for the season.[32][non-primary source needed] At the end of the season, Brooks was named for the first time to the NBA All-Defensive Second team.[33]
During Memphis' 2023 NBA playoffs series against the Los Angeles Lakers, Brooks openly criticized his opponent LeBron James for being "old", drawing scrutiny.[34][35] Brooks was ejected after committing a flagrant 2 foul just 17 seconds into the second half of the Grizzlies–Lakers Game 3 matchup because of hitting James with a hit below the belt.[36][37] Memphis would go on to lose the series in six games.[38]
Houston Rockets (2023–present)
On July 8, 2023, Brooks was acquired by the Houston Rockets as part of a sign-and-trade agreement.[39] On October 26, he made his Rockets debut, scoring 14 points along with four rebounds and two assists in a 116–86 loss to the Orlando Magic.[40] On February 14, 2024, Brooks recorded a 19 point, 10 rebound double-double during a 121–113 loss to the Memphis Grizzlies.[41]
On May 24, 2022, Brooks was one of fourteen players to agree to a three-year commitment to play with the Canadian senior men's national team, aiming to break a decades-long trend of failing to qualify for the Olympic basketball tournament.[42] They achieved this goal at the 2023 FIBA World Cup, and won the bronze medal, Canada's first global tournament medal in basketball since 1936. Brooks played a crucial role, recording a team-best 39 points in their victory over the United States.[43] This was a single-game scoring record for a Canadian player at the World Cup, surpassing Carl Ridd's previous high of 37 at the 1954 edition.[44] Brooks was named Best Defensive Player of the tournament by FIBA.[45]