The long wait for Andrea Bargnani’s return is almost over.

A pain-free Bargnani practiced fully for the first time since straining his left hamstring in the Knicks preseason opener, and coach Derek Fisher pegged Saturday against the winless Sixers at the Garden as Bargnani’s potential season debut.

Ironically, Bargnani’s last regular-season game came against the Sixers last Jan. 22, when he suffered a season-ending elbow tear after tumbling to the floor on a drive. Bargnani missed the final 40 games. If he’s back Saturday, that would make 53 straight regular-season games he’d have missed, topping the 42 he has played in orange and blue.

“I did everything,’’ Bargnani said. “I come back when the doctors say I’m clear, and I’ll do everything to try to help the team. [Monday] I felt good doing everything. It’s great to be with my teammates and do the routine again. I can’t wait.’’

Bargnani said he had no pain in his right hamstring and has been cleared for contact, though there wasn’t much at Monday’s practice. “Once he gets contact, we’ll see if he’s ready,’’ Fisher said.

Bargnani started at power forward in the preseason opener, and Fisher had hoped the 7-footer would man that position this season.

Fisher has used four different starting power forwards: Quincy Acy, Jason Smith, Amar’e Stoudemire and Carmelo Anthony for two games in a small lineup.

Without starting point guard Jose Calderon and Bargnani, the Knicks have struggled to a 3-8 start and play five of the next six games on the road, including Tuesday in Milwaukee and Wednesday in Minnesota.

“It’s great to be with my teammates and do the routine again,’’ Bargnani said. “I can’t wait.’’

The Knicks don’t practice after back-to-backs, but Fisher said he may bring in extra players to scrimmage with Bargnani Thursday before their next scheduled practice Friday.

Knicks president Phil Jackson views Bargnani as a perfect fit in the triangle as a jump-shooting big man.

“Whenever he’s back, his versatility is huge for us on both ends of the floor,” Fisher said. “I think he can guard multiple positions and offensively he can play multiple positions. He’s another guy on the floor that defenses have to think about how they want to cover him. He makes the game easier for Carmelo, J.R. [Smith], Iman [Shumpert], Jose. So we’re excited to get him back soon hopefully, and start to kind of rebuild our team again.”

Iman Shumpert (left hip contusion) may play Tuesday against the Bucks after missing Sunday’s victory over the Nuggets, and will test his leg during Tuesday’s shootaround in Milwaukee.

“I feel a lot better, each day getting a lot better,’’ Shumpert said. “It’s sore. I think I’m going to try it out at shootaround like I tried it [Sunday] at shootaround and see if I can go. If I can’t go out there and be athletic, I’m not going to do it.’’

J.R. Smith started at shooting guard in place of Shumpert and flourished.

The Knicks’ defensive confusion was first exposed against Jason Kidd’s surprising Bucks, who rang up 125 points in a preseason win at the Garden. Milwaukee won in Miami on Sunday to move to 5-5. Rookie small forward Jabari Parker, the No. 2 overall pick, is averaging 10.6 points.