Isaiah Washington is scheduled to return to the Grey's Anatomy set as early as Thursday for the first time since entering counseling after making a homophobic slur, a source tells PEOPLE.

Washington, who plays Dr. Preston Burke, has not been on the set since Jan. 23, the day before he issued a statement saying he would seek counseling "as a necessary step toward understanding why I did what I did and making sure it never happens again."

He also missed picking up a trophy at Sunday's Screen Actors Guild Awards that honored the Grey's cast for drama. "There's a little awkwardness here," costar Katherine Heigl said before the show. Best actress winner Chandra Wilson alluded to his absence, saying in her acceptance speech, "It's about the 10 cast members sitting over there and the other one in rehab."

A source familiar with the Grey's Anatomy production schedule tells PEOPLE that Washington has confirmed he'll arrive for his next call time, now set for Thursday, though the show's production schedule changes.

Washington, 43, has been at the center of controversy since using a homophobic slur to refer to costar T.R. Knight, who is gay. After a firestorm of criticism, Washington apologized, then on Jan. 23 announced: "I have begun counseling."

"I appreciate the fact that I have been given this opportunity and I remain committed to transforming my negative actions into positive results, personally and professionally," he said.

Reps for the show and Washington declined to comment.