As the Nets milled around the visitor’s locker room inside Bankers Life Fieldhouse in Indianapolis Saturday night, preparing to go home after losing 97-96 to the Pacers, Deron Williams sat at his locker with both his feet encased in ice and a sour look on his face.

After going 3-for-12 on his way to 13 points and six assists in his return to the starting lineup, Williams admitted his confidence — always an issue for the franchise star — isn’t where he needs it to be.

“It’s not my highest,” he said with a sheepish smile. “It’s been tough … just being in and out of the lineups, missing two weeks here and there.

“I feel like I get my legs back, get my legs in shape, and then I go out again. Then I’ve got to just do it all over again. It’s just been a struggle.”

It’s seemingly been a never-ending struggle for the franchise point guard since the Nets moved to Brooklyn in the summer of 2012. After Williams agreed to become the face of the franchise by inking a five-year, $100 million max contract that summer, he has battled issues with both of his ankles.

Williams dealt with inflammation in them last season, eventually undergoing three rounds of cortisone shots as well as a round of platelet rich plasma treatment before the All-Star break. That allowed him to enjoy a brief renaissance. He averaged 22.9 points and 8.0 assists in the season’s second half, and after all the moves the Nets made last summer to surround him with talent, he expected to come into this year healthy and ready to return to elite point-guard status.

Instead, Williams suffered a sprained right ankle in an in early September workout that kept him out for virtually the entire preseason. He has since suffered multiple sprains of his left ankle that have forced him to sit out 16 games this season — including five last month to undergo another round of cortisone shots and PRP treatment.

But the fact Williams, who will be back in the starting lineup for a second straight game Monday night when the Nets face the 76ers in Brooklyn, was able to bounce back from his ankle issues a year ago isn’t making dealing with his current woes any easier.

“That makes it worse, because I thought this was behind me,” he said, shaking his head, “so to go through it again is frustrating.”

Part of dealing with that is the constant coming and going from the lineup, as well as the rebuilding of his stamina each time he has to leave the lineup. His legs have repeatedly proved to be an issue in back-to-back games, when he has consistently shot worse (43.7 percent from the field, 36.7 percent from 3-point range) than he has in games when the Nets haven’t played the night before.

“I think back-to-backs have been tough the whole year on me,” he said on Saturday. “I played a lot of minutes [Saturday], and I could feel them getting heavy, but there’s no excuses. That’s my job. I’ve got to find ways to push through it.”

Since coming to the Nets in a blockbuster trade with the Jazz in 2011, Williams often has spoken about having to work on not beating himself up whenever he has a bad game, and teammates have tried to help him with that.

It was a problem Williams again acknowledged after Saturday’s loss.

“That’s what I’ve got to stop doing,” he said. “I don’t know. That’s just me. That’s how I am. Somehow, I’ve got to do it.”