​Marc Stein: The Mavericks say CEO Rick Welts, who was lured out of retirement in December 2024 to lead the team’s new arena project, will step down at year’s end and be succeeded by former Timberwolves and 49ers CEO Ethan Casson on Jan. 1, 2027. Welts, 73, is a 2018 @Hoophall inductee who previously worked for the Warriors, Suns, Sonics and league office dating the 1970s.x.comThis article originally appeared on Hoops Hype: The Mavericks say CEO Rick Welts, who was lured out of …