The Oklahoma City Thunder open the 2018-19 regular-season on Tuesday against the mighty Golden State Warriors, and the team will be without the services of star point guard Russell Westbrook.

Westbrook underwent surgery on his right knee on Sept. 12 and is still not doing full contact, according to Thunder head coach Billy Donovan. As of now, Westbrook is only able to do “controlled contact.”

Russell Westbrook has averaged a triple-double for two seasons in a row, and won the 2017 MVP award. Last season, Westbrook posted averages of 25.4 points, 10.1 rebounds and 10.3 assists per game during the regular-season. The 29-year-old shot 44.9 percent from the field, 29.8 percent from beyond the arc and 73.7 percent from the free-throw line.

Westbrook's surgery in September was the fourth procedure the explosive guard has had on his right knee following a collision with guard Patrick Beverley in the 2013 playoffs which resulted in a meniscus tear. Westbrook underwent three surgeries on the knee in a nine-month span. However, it had been four and a half years since any surgery was performed on Westbrook’s knee prior to the September procedure.

The Thunder will start Dennis Schroder at the point guard spot until Westbrook returns. OKC acquired Schroder this offseason from the Atlanta Hawks in the Carmelo Anthony trade. The 25-year-old averaged 19.4 points, 3.1 rebounds and 6.2 assists per game with the Hawks last season.