Westbrook hasn't played since tearing knee cartilage during the second game of last season's playoffs. General Manager Sam Presti said Sunday that Westbrook has met the requirements for his return.
Westbrook first underwent surgery April 27 and again on Oct. 1 to remove a loose stitch from the first operation.
At the time, the Thunder (1-1) said he would miss the first four to six weeks of the season. Instead, he missed only two games -- a win at Utah on Wednesday and a 100-81 defeat at Minnesota on Friday.
The loss was Oklahoma City's worst since a 111-88 defeat at Orlando on Feb. 25, 2011.
"Them not having Westbrook, that's taking away 25 (points), seven (rebounds) and six (assists) or some crazy number like that," Timberwolves star Kevin Love said. "It's a whole different dynamic when they have Westbrook on the team."
The Thunder may be able to bounce back Sunday in what has proved to be a favorable matchup over the years. Oklahoma City's 10 straight wins over Phoenix (2-0) have come by an average of 14.8 points, the latest being a 97-69 victory Feb. 10.
The Thunder have won the past two meetings by 29.5 points per game.
"I'm worried about guys playing hard, competing hard and playing for your team every time down the court," coach Scott Brooks said. "But it's early. We've got a game right around the corner and we've got to play much better."
Taking down the Suns, though, could prove more difficult this time around. Phoenix, in its first season under coach Jeff Hornacek, is off to its best start since opening 4-0 in 2009-10.
After beating Portland 104-91 in their first game Wednesday, the Suns pulled out an 87-84 victory over the Jazz two nights later on Eric Bledsoe's tiebreaking 3-pointer with 0.7 seconds left. Bledsoe, acquired from the Los Angeles Clippers in the offseason, missed 10 of his first 11 shots before scoring the final 14 points for Phoenix.
"It feels great," Bledsoe told the team's official website. "I was preparing all summer. All summer I was working and to finally get this opportunity is a blessing."
Second-year forward Miles Plumlee has also provided a huge boost with 31 points, 28 rebounds and six blocks through the first two games.
Phoenix may need to lean on Bledsoe and Plumlee all the more with Goran Dragic uncertain to play. Dragic, who scored 26 against the Trail Blazers, was limited to five and shot 2 of 11 against the Jazz before exiting in the third quarter with a right face contusion.
"He just didn't look right," Hornacek said.
The Suns have dropped five in a row and six of seven at Oklahoma City. The Thunder have won their last four home openers.
Russell Westbrook was supposed to be out the first 4-6 weeks of the season but is returning after missing just 2 games.
Westbrook had 11.6 win shares last season... Had he missed 6 weeks, he would have missed 21 games. Taking into account his win shares, that would have cost the Thunder roughly 3 wins.
Last season, just 4 games separated the 1 through 5 seeds in the Western Conference.
Getting Westbrook back could essentially be the difference between home court throughout the playoffs and being on the road for the first round.
Russell Westbrook's season debut was pretty similar to another star point guard, Derrick Rose. Both were decent when shooting near the basket, but when they were 5 feet or more from the hoop, both struggled. Westbrook was just 1-of-7 from 5 feet or more Sunday, while Rose in his debut was 1-of-8.