Williams missed Games 3-5 with left hamstring strain management. He suffered the injury in Round 1, but re-aggravated it after just seven minutes of game time in Game 2 of the West Finals.
Despite being active, Williams will not be in the starting lineup. The Thunder will run the same opening five as Game 5, with Jared McCain in Williams’ usual spot.
The one-time all-star has battled injuries throughout this season. He appeared in just 33 regular-season games and has missed nine playoff contests, including all of Round 2.
Williams is averaging 24.3 minutes, 17.8 points, four rebounds, 3.3 assists and 1.2 steals in the four post-season games he has played in.
Despite Williams returning, Ajay Mitchell remains sidelined for the third straight game with a calf strain.
The Thunder can close out the Western Conference Finals over the Spurs on Thursday and head to their second consecutive NBA Finals.