McDaniels played basketball for Federal Way High School in Federal Way, Washington. As a freshman, he was teammates with his older brother Jalen and helped Federal Way win its second straight Class 4A state championship.[1] McDaniels averaged 2.4 points and 1.8 rebounds per game on the varsity team and was forced to shoot with his left hand due to a right elbow injury.[2] In his first two years, he helped his team win 63 consecutive games, the longest win streak in state history since 1977.[1]
As a junior, McDaniels guided Federal Way to a runner-up finish at the 4A state tournament.[3] In the season, he averaged 21.3 points, 10 rebounds, 4.6 assists, and 3.3 blocks per game and earned USA Today All-USA Washington first team honors.[4] In May 2018, McDaniels saw breakout success at the Nike Elite Youth Basketball League (EYBL) with Seattle Rotary, bolstering his position as a top recruit in the 2019 class.[5][6]
By the end of his high-school career, McDaniels was considered a consensus five-star recruit and the best power forward in the 2019 class.[13]ESPN and Rivals ranked him among the top 10 players in his class.[14][15] On May 22, 2019, McDaniels committed to play college basketball for Washington. He had also received strong interest from Kentucky during the recruiting process.[16]
Heading in to the college season, McDaniels was considered a possible number-one pick in the 2020 NBA draft.[17] In his collegiate debut, a 67–64 upset of Baylor, he had 18 points and seven rebounds.[18] He had a season-high 22 points against Ball State. As a freshman, McDaniels averaged 13 points and 5.8 rebounds per game while starting 21 games but began coming off the bench midway through conference play. After the season, he declared for the 2020 NBA draft.[19]
On April 9, 2023, McDaniels sustained a fracture in his right hand after he punched a wall following a 113–108 win over the New Orleans Pelicans.[22]
On October 23, 2023, McDaniels signed a five-year contract extension with the Timberwolves worth $136 million.[23] During an on-court altercation at a November 14 game between the Timberwolves and the Golden State Warriors, McDaniels pulled Klay Thompson over and ripped his jersey, which started a brawl. Timberwolves center Rudy Gobert attempted to pull Thompson away from McDaniels, but Draymond Green put Gobert into a chokehold. McDaniels was ejected from the game and fined for the incident.[24][25]
On April 23, 2024, McDaniels led all scorers with a playoff career-high 25 points in a 105–93 victory over the Phoenix Suns in the first round.[26] The Timberwolves went on to sweep the Suns and advance to the second round.[27]
McDaniels's older brother, Jalen McDaniels, played basketball for Federal Way High School, where he was a four-star recruit,[29] before joining the University of Washington at the college level. He was selected by the Charlotte Hornets in the second round of the 2019 NBA draft.[30] McDaniels is a cousin of former NBA player Juwan Howard.[1] Both his father, Will McDaniels, and his mother, Angela Jackson, are originally from Chicago.[2]