OAKLAND, Calif. — Golden State Warriors guard Monta Ellis will be out at least three months after severely spraining his ankle during an offseason workout.

Ellis, who got a six-year contract extension worth $66 million from the Warriors this summer, sprained his ankle and tore a deltoid ligament while working out at his home in Jackson, Miss., Warriors spokesman Raymond Ridder said.

Ellis underwent surgery today to repair the ligament. Ellis' ankle will be immobilized for six weeks, followed by at least six weeks of off-court rehab before the guard can return to basketball workouts.

Ellis will miss training camp and the Warriors' preseason schedule, which includes a trip to China, along with at least the first month of the regular season.

Ellis is expected to play a major role this season for the Warriors after Baron Davis' abrupt departure for the Los Angeles Clippers as a free agent. Golden State showed its commitment with a huge contract extension for Ellis, who is likely to assume Davis' role as the point guard and catalyst of coach Don Nelson's uptempo offense.

Ellis averaged 20.2 points, 5.0 rebounds and 3.4 assists last season, all career bests for the winner of the NBA's most improved player award in 2006-07.