LOS ANGELES >> The Los Angeles Lakers fired general manager Mitch Kupchak on Tuesday and put Magic Johnson in charge of basketball operations in a major shake-up of the struggling franchise’s front office.

Lakers owner Jeanie Buss also removed her brother, Jim, from his job as the Lakers’ executive vice president of basketball operations.

Jeanie Buss then promoted Johnson, the Hall of Fame point guard who returned to the franchise earlier this year in an executive role. Johnson is the Lakers’ new president of basketball operations, reporting directly to Jeanie Buss.

Jeanie Buss made the extraordinary moves two days before the NBA’s trade deadline. The Lakers are 19-39 this season, plummeting out of contention after an encouraging 10-10 start under new coach Luke Walton, who got a strong vote of confidence from Jeanie Buss.

In a statement, Jeanie Buss said she “took a series of actions I believe will return the Lakers to the heights Dr. Jerry Buss demanded and our fans rightly expect,” referring to her father, the late Lakers owner.

“Our search for a new general manager to work with Earvin and coach Luke Walton is well underway, and we hope to announce a new general manager in short order,” Jeanie Buss added. “Together, Earvin, Luke and our new general manager will establish the foundation for the next generation of Los Angeles Lakers greatness.”

Kupchak has been the 16-time NBA champion franchise’s GM since 2000, when Jerry West left the club. Kupchak had been in the Lakers’ front office for 30 years, including the last 17 as general manager — the longest current stretch running a front office in the NBA.

Jim Buss had been in the Lakers’ front office for 19 years, including 12 in charge of basketball operations alongside Kupchak.

The Lakers are mired in the worst four-year stretch in franchise history, missing the playoffs in three consecutive years with their three worst records ever. They finished 17-65 last season, a franchise low in the last year of Kobe Bryant’s two-decade run with the franchise.

Johnson’s return made Jim Buss’ departure seem quite likely, particularly given Jim Buss’ vow several years ago to leave the franchise if they weren’t in contention for a Western Conference title by this year or next.

Johnson has never been a decision-making NBA executive, but he has been a successful businessman and investor since his playing career ended. He also briefly coached the Lakers, but dropped his ceremonial title as a team vice president last June after his frequent criticisms of Jim Buss and former coaches. He sold his ownership stake in 2010.

The departure of Kupchak is even more dramatic. The former Lakers center had worked with Jerry West and Jim Buss in relative harmony for years with the tradition-bound Lakers.

The Lakers’ recent ineptitude didn’t hurt their place as Los Angeles’ most beloved sports franchise and a worldwide brand, but Jeanie Buss finally tired of the apparent lack of progress. The Lakers have a talented young core with D’Angelo Russell, Julius Randle, Brandon Ingram and Jordan Clarkson, but haven’t been able to translate that potential into wins despite playing an exciting style under Walton.

The Lakers also parted ways with longtime top public relations executive John Black.