Davis attended Muskegon High School in Muskegon, Michigan. In his final season, he recorded 4 points and 12 rebounds in the state regional finals, as Muskegon escaped Hudsonville in quadruple-overtime. He played his final game for the Big Reds on March 24, 2015, in a 52-75 quarterfinals loss to Everett High School. He contributed 12 points, 8 rebounds, and 5 blocks. It was played only three miles from the Michigan State University campus. Davis said after the loss, "It was very important . We came out ready to play, but the game just didn't go our way." The game was attended by MSU assistant basketball coach Dwayne Stephens, who helped recruit him to his team. Davis also got the chance to meet Spartans players before competing. As Muskegon's star left his team, head coach Keith Guy said, "The future is bright. Two games don't define his career." By the end of the season, Davis was named Mr. Basketball of Michigan for 2015. In the balloting, he earned a total of 5,223 points. Arthur Hill's Eric Davis and Everett's Trevor Manuel finished after him, getting 3,757 and 2,837 points respectively. The award was won by two straight players from Muskegon High School, Deshaun Thrower winning in 2014. Big Red coach Guy complemented his team, saying, "To have another kid win it for the second consecutive year, it shows how far our program has come the last three years." Davis was given his personal Mr. Basketball trophy between the quarters of the Michigan state title game, in which Saginaw's Arthur Hill played against Detroit's Western International. He said in disappointment, "I'd much rather be on the floor playing right now." On April 1, 2015, Davis competed in the 2015 McDonald's All-American Boys Game, playing for the West team. He played alongside the likes of Stephen Zimmerman and Jalen Brunson and against Diamond Stone and Cheick Diallo. Davis finished the game with 6 points and 9 rebounds, leading his team in the latter category. In January, when he was named to the game, Bank Hoops scout Steve Bell said, "This is huge for West Michigan." The forward was the first player from that region to appear at the stage since Matt Steigenga in 1988.
College career
Davis played one season at Michigan State, averaging 7.5 points per game, 5.5 rebounds per game, and 1.6 blocks per game. Davis started 16 of the final 17 games of the season for the Spartans. Davis was a key part to Michigan States record setting start to the season, Big Ten Tournament Championship, and MSU's 2nd overall final rank in the AP Poll. He set the school freshman record with 64 blocked shots, second-most in a single season in program history.
Davis declared for the draft on April 12, 2016. Davis and teammate Denzel Valentine were selected to attend the 2016 NBA Combine. Davis hired Bill Duffy as his agent. Jonathan Givony from DraftExpress had the following to say on Davis: "Although he doesn't produce eye-popping numbers, his ability to switch on screens and stay in front of players big and small has been huge for the Spartans, especially late in games. ... Casual fans should try and get to know him better as the Tournament moves on, provided Michigan State is able to advance, as there's a pretty good chance the NBA will be calling for him when the season is over." While Davis was consistently labelled as a lottery selection all the way until the day of the draft, he was chosen by the Boston Celtics with the 31st overall pick. He therefore became the first green room invitee to not hear his name get called in the first round since Maciej Lampe in 2003's NBA draft. Davis' rights were later traded to the Memphis Grizzlies on draft night.
Memphis Grizzlies (2016–2018)
On July 12, 2016, Davis signed a fully guaranteed three-year, $4-million contract with the Memphis Grizzlies. The deal marked the richest guaranteed salary for an American-born second-round pick in NBA history. On December 15, 2016, he was ruled out for six to eight weeks with a torn plantar fascia in his left foot. During his rookie and sophomore seasons, Davis received multiple assignments to the Iowa Energy and the Memphis Hustle, the Grizzlies' G League affiliates.
On July 17, 2018, Davis was traded, along with Ben McLemore, a 2021 second-round pick and cash considerations, to the Sacramento Kings in exchange for Garrett Temple. On September 22, 2018, Davis was waived by the Kings. On October 11, 2018, Davis signed with the Golden State Warriors. The Warriors released him on October 12. He was then added to the Warriors’ G League affiliate, the Santa Cruz Warriors.
On March 19, 2019, Davis was called up to the Atlanta Hawks and signed a 10-day contract. He signed a second 10-day contract on March 29. On April 8, 2019, following the expiration of his second 10-day contract with Atlanta, Davis signed a multi-year contract with the Hawks. On June 10, 2019, Davis was waived by the Hawks. He averaged four points and four rebounds in nine games. On the same day, Davis was claimed off free-agency waivers by the Houston Rockets. On July 30, 2019, he was waived.
Second Stint with Santa Cruz Warriors (2019–present)
On October 29, 2019, Davis was included in the training camp roster of the Santa Cruz Warriors. On February 23, 2020, Davis posted 18 points, 11 rebounds, two assists, two steals and two blocks in a loss against the Stockton Kings for his sixth straight double-double. He averaged 11.5 points and 8.2 rebounds per game in 2019-20.
