The Oklahoma City Thunder are going to be without a big piece of their roster in Tuesday's season opener.

The team announced that superstar guard Russell Westbrook has been ruled out for Tuesday's game against the Golden State Warriors. Westbrook had originally been listed as out on the team's injury report for the game, but the Thunder were making a final assessment on Tuesday.

Westbrook underwent arthroscopic surgery on his right knee on Sept. 12, with the plan to be re-evaluated in four weeks. As of Oct. 11, head coach Billy Donovan revealed that the former NBA MVP had yet to be cleared for full contact and had been working with the Thunder's medical team in "controlled situations."

Westbrook had originally experienced stiffness in his right knee, which led to the team opting for him to have the procedure before the season. If Westbrook had waited to have the procedure done following the 2018-19 campaign, it could've been something that potentially lingered all season.

Westbrook is coming off another MVP-caliber season where he averaged 25.4 points, 10.3 assists and 10.1 rebounds. It was the second consecutive season in which he averaged a triple-double.

With Westbrook out of the lineup, Dennis Schroder, who the team acquired in the three-way trade involving Carmelo Anthony over the summer, has served as the Thunder's starting point guard during the preseason. Schroder has definitely thrived in the role as he's averaged 15.3 points, 5.5 assists and 4.3 rebounds. 

Schroder likely will serve as the starting point guard in Westbrook's absence against the Warriors. On Monday, Schroder spoke to the media and stated that he was willing to do "whatever it takes" to help the Thunder win, whether Westbrook was able to play or not.

While the Thunder will be without the services of their All-Star point guard, starting center Steven Adams has been cleared to play in Oklahoma City's season opener after initially being listed as questionable by the team after dealing with lower back stiffness and missing practice on Monday.