"We are thrilled to announce this contract extension with Devin", Suns general manager Ryan McDonough said in a statement.
Booker averaged 24.9 points, 4.7 assists and 4.5 rebounds in his third season with Phoenix and shot 38.3 percent from 3-point range.
The Suns are banking on Booker to be the player that leads them back to winning ways in the coming years and eventually back into the playoffs.
Sacramento Kings number two overall draft pick Marvin Bagley III poses with his jersey during an introduction press conference at Golden 1 Center. "Devin and the team both wanted to extend this agreement with the club as long as we possibly could". "I loved calling Phoenix home the last 3 seasons as this team & community are special to me".More news: Lewis Hamilton hails one of the finest moments of his career
Booker, 21, is one of the NBA's elite young scorers and his extension cements his status as a major piece of the Suns' franchise. Thank you to the Suns for drafting me and believing in me.
On March 24, 2017, Booker scored a franchise record 70 points at Boston, becoming just the 6th player in National Basketball Association history to record a 70-point game. "I look forward to the future [and] pursuing a title as a Sun".
In his lone season at Duke, Bagley earned consensus first-team All-America honors for averaging 21.0 points and 11.1 rebounds per game.