If any fighter appeared to be finished, it was Chris Byrd in his last fight.

The small-framed former heavyweight titleholder whittled himself down to the 175-pound light heavyweight limit to face Shaun George last May but barely had the energy to throw a punch in the fight. He was stopped in nine pathetic rounds.

That appeared to be that: Byrd’s wife and manager Tracy announced that he would retire and he gave no indication that he felt differently. And then, like so many before him, he decided over time that he couldn’t stay away.

Thus, he’s in Stuttgart, Germany, sparring with Vitali Klitschko and preparing to reinvent himself one more time as a cruiserweight at 38 against inexperienced Matthias Sandow on Saturday.

“That was an emotional decision (Tracy) made at the moment,” he said over the phone from Germany. “I came home, prayed about it, went over it with my wife and the Lord weighed on my heart that I wasn’t done yet. I was surprised.”

So were many others.

A listless Byrd was outworked by Alexander Povetkin in 2007 and, amid hopes of storming the light heavyweight division, he fell flat against George. The reaction was universal: It’s time to say goodbye, Chris.

“I can’t listen to everybody,” he said. “I give credit to the guys I fought in my last two fights; they did what they had to do. I didn’t give myself a 100 percent chance to win, though. In one (against Povetkin) I got hurt and in the other I lost too much weight.

“I just lost too much weight (an estimated 40 pounds) too fast. I was thinking that I’d be dominant but I didn’t do it the right way.”

Byrd (40-5-1, 21 knockouts) admitted that he was nervous about coming back after his performance against George.

However, he feels as if he’s at his natural weight – about 187 pounds this week, which would make him a small cruiserweight – and proved to himself when he resumed training that he wasn’t the depleted fighter who lost to George.

“Before I came here to Germany, I went and sparred with a guy who normally gives me only a couple rounds; it’s a chore for him to get into the ring. And I was nervous to spar with him,” Byrd said. “I was thinking, ‘Do I still have anything left? Why am I nervous?’

“The first time I sparred, though, I was like, ‘Man, everyone said you’re done, washed up, but I still have a lot left.’ It was the weight. The doubt is gone.”

Byrd was training but had no fight in the works when Klitschko called a little over a month ago to ask whether he’d come to Germany and spar with him. Juan Carlos Gomez, Klitschko’s opponent in the main event Saturday, is a slick southpaw like Byrd.

Klitschko, whose WBO heavyweight title Byrd took in 2000 when Klitschko retired on his stool with a shoulder injury, was so impressed with his old foe in sparring that he asked whether he’d fight on the card. He accepted.

“I’m sparring with him and everyone in the gym is saying, ‘Man, we’re getting glimpses of the old Chris Byrd.’ I was doing things I used to do,” Byrd said.

Sandow (4-3, three KOs) has a fraction of Byrd’s experience, which seems to be what Byrd had in mind. He wants to ease into this new – and perhaps final – phase of his career.

“If I can’t compete, I won’t fight,” he said. “I’m not about boxing just to keep going. I want to be in the mix. I thought I never got credit being so small in the heavyweight division. I wanted to leave a mark. I’m not a big guy, though, fighting these monsters.

“Everyone criticized me for not being a big puncher. Now, at cruiserweight, I’m looking to win a title. I want to be a champion again.”

Michael Rosenthal can be reached at [email protected]