Although he cut an impressive physical presence, Al Horford’s right pectoral muscle had been tearing for years, perhaps as far back as his days at the University of Florida.

The muscle tore completely Dec. 26 and ended Horford’s season after 29 just games, marking the second time in three years that the freak injury cut short a campaign for the All-Star center.

Horford is again returning from surgery as the Hawks open training camp in advance of the 2014-15 NBA season. He will be limited during training camp, including being held out of contact drills, and will be brought along slowly in anticipation of being ready for opening night.

“I’ll be fine,” Horford said Tuesday on the Hawks’ first day of training camp. “Honestly, the coaches and the trainers just want to be safe and I understand. I’m very competitive, so I really want to be out there. We have to be smart about this, so I’m taking my time.”

Coach Mike Budenholzer added that the Hawks will err on the side of caution in the final stages of Horford’s rehabilitation.

Surgery revealed scar tissue in Horford’s right pectoral. He said doctors believe the tear was a result of his weightlifting workouts from his college days and he has since changed his technique. He no long works on his upper body with bench presses and overhead lifts, concentrating now on his core and legs more than his upper body.

Horford can participate in much of each practice, but will be held out of contact drills at least for the first week of exhibition games. Horford said he will play at some point during the exhibition season.

“I want to play,” Horford said. “I want to make sure I get in there and get in some kind of rhythm. You can practice, but it’s not the same as games.”

Still, Horford acknowledges there will be some trepidation until he takes that first hit. After that, he anticipates it will be business as usual.

There were moments of frustration during the latest round of rehabilitation. However, those bouts did not come as often as in 2011, when he played in only 11 regular-season games before tearing his left pectoral muscle. Horford said during the latest rehabilitation, he has concentrated on evaluating his game, determined to have something constructive come from the disappointment.

“I think something positive came out of it,” Horford said. “Now, I can move past it and have a healthy good season. My biggest thing was taking this challenge and growing and learning from it. I felt like I was able to do that.”

Horford was leading the Hawks in scoring (18.6) and rebounds (8.4) at the time of the injury. He scored in double figures in 28 of his 29 games and had nine double-doubles.

The Hawks were third in the Eastern Conference when they lost Horford and ended up eighth, making the playoffs with a sub-.500 record. Horford watched as the Hawks pushed the top-ranked Pacers to seven games before letting the series slip away, a possible series-clinching Game 6 loss at home being particularly painful.

The Hawks had trouble scoring down the stretch with the game on the line. Certainly, having Horford available would have helped in those situations.

“It’s like anything, the more good players you have when it comes down to the end of the game and you have multiple options, Al, Paul (Millsap) or Jeff (Teague) or Kyle (Korver) or even DeMarre (Carroll),” Budenholzer said. “The more weapons, the more options we have, the better. We are built more to have multiple options than just one guy. But obviously, Al is a heck of a guy to have as an option.”

Returning as the starting center won’t be an issue for Horford. At 6 feet 10 and 250 pounds, many, including Horford, wanted to see him move to power forward. He no longer thinks that way under Budenholzer’s offensive system.

“The league is changing so much and we are playing at a faster pace,” Horford said. “In this offense, the way I look at it, the (No.) 4 and the 5 are very interchangeable. Paul and I can both play inside and out. It works here. Before it might not have worked, but here it works.”