Al Harrington, above right in a 2012 game when he played for the Nuggets, shed 27 pounds working himself back into shape during the offseason. (Chris Carlson/AP)

Bags of ice strapped to both knees, Washington Wizards free agent pickup Al Harrington gathered himself for a gingerly stroll through the gym at George Mason’s Patriot Center. Harrington, 33, had just completed his second day of training camp, and he couldn’t contain an enormous smile when asked about Coach Randy Wittman’s decision to have one practice each day instead of the usual two.

“I’m so happy. I’ll tell you, if we had two-a-days, I probably wouldn’t be able to do them. Me and Coach would have to work out a deal,” the 15-year veteran forward said with a laugh. Even the three-hour practice to open camp Saturday was more grueling than he expected: “I don’t know why. I felt like I got hit by a bus.”

But Harrington will take that feeling any day. At this time last year, he was worried his career might be over as he dealt with a staph infection following a seemingly routine operation in April 2012 to repair a torn meniscus in his right knee.

“I remember last year thinking, ‘I would give anything to play and be healthy again,’ ” Harrington said. “So every time I get down or feel like I don’t want to do something, I always think about how I felt. So it’s just a great feeling to be out here.”

The knee ailment sidelined Harrington for nearly 10 months until he made his debut in February with the Orlando Magic. He was limited to 10 forgettable games in Orlando, recording his least productive season in more than a decade. But Harrington’s fight to get back on the court last season pushed him to train more rigorously in the summer — he lost 27 pounds — and to find a team where his skills as a reliable scorer with three-point range would be valued.

After the Magic waived Harrington in August, he resisted overtures from Chicago and the Los Angeles Clippers to join the Wizards, who were in search of a big man capable of stretching the floor. John Wall and Nene, Harrington’s former teammate in Denver, both put on a heavy recruiting job once he became available.

“He’s a great guy. I’m so happy to have him,” Nene said of Harrington, who has averaged 13.7 points per game and shot 35.2 percent on three-pointers in his career with Indiana, Atlanta, Golden State, New York, Denver and Orlando. “I call him the sniper out of the corner. He’s going to be there to take that shot, and I know he will make it. After he had that injury, he’s thirsty. He’s hungry to prove a point.”

Harrington could prove to be valuable pickup for the Wizards, who already are short-handed up front. Center Emeka Okafor is out indefinitely with a neck injury, forward Chris Singleton is out another five weeks with a broken foot and Otto Porter Jr. and Trevor Booker have been limited by minor injuries in the first two days of camp.

The 6-foot-9 Harrington has played power forward for most of his career, but he has some experience guarding former NBA centers Shaquille O’Neal and Yao Ming from his days as a small-ball center with Golden State.

“It don’t matter. Whatever it takes,” he said. “Obviously, I feel I’ll be at a disadvantage guarding some of the bigger guys. But it’s definitely going to be a disadvantage for guys guarding me. I’m up for the challenge. But I lost too much weight. I got to put some more weight on to play with these guys.”

No matter what position he plays, Harrington said he would prefer to come off the bench for the Wizards. “I feel like a starter, so I feel like when I come off the bench, I’m playing against second-level guys and I’m better than all of them all the time,” Harrington said with a laugh. “So it’s an advantage, to be all the way honest.”

Harrington might feel a little fatigue from working himself back into game shape, but nonetheless he is one of the last players to leave the court, circling the three-point line to put up extra shots. He believes his shooting ability will be beneficial for Wall and the rest of the Wizards.

“It’s going to space the floor, going to give those guys a lot of room to get their game on,” Harrington said. “So I’m just excited to be out there, allowing them to do that, and when they kick it out there to me, I’ve got to do my job and make shots. . . . They got some good pieces. I would just love to be one of the guys to come in and help them get over the hump.”