SCOTTSDALE, Ariz. -- D-backs left-hander Clay Zavada reported for work Wednesday morning and said his absence from camp the past few days was due to a personal matter.

"Basically, all it is was a personal matter with my family and had nothing to really do with baseball," Zavada said. "I was going through some things and needed some time, so I came in, I talked to [manager Kirk Gibson] and straightened everything out, and I'm here now and ready to play."

Zavada's agent, Barry Meister, said Tuesday that his client had experienced some discomfort in his shoulder, which was the reason for his absence. Zavada underwent Tommy John surgery last May and is scheduled to throw off a mound for the first time later this week.

When asked about his shoulder, Zavada said, "Well, I mean everybody has a little discomfort. Spring Training, that's what it's all about -- getting ready."

"I think the rehab process is often difficult for guys," general manager Kevin Towers said Tuesday. "And the last week or so throwing the ball, he probably didn't feel right and wasn't real happy with where he was at and was contemplating whether he should go through the grind of the rehab process. And I think the more he had time to think about it, he decided he's going to give it a shot.

"[He] probably had a 24- to 48-hour period where he had some doubts, but it sounds like he's focused on coming here and continuing the rehab process and hopefully pitching in the big leagues again."

Towers said that Zavada's absence would not be held against him going forward and that he hoped the left-hander could get into a game before the end of the spring.

That's something Zavada would certainly welcome as he admitted the rehab process is a challenge.

"It's a real patient process, and patience is something I need to work on," Zavada said. "I'm a ramped-up, amped-up guy and I really just want to come back and kick some butt. Gibby's great. He's got a good attitude and it's good to be around. The sun is shining, the balls will be flying. It's good to be here and I'm happy. I don't have anything else to say."

Zavada was a key contributor to the D-backs' bullpen in 2009, when he compiled a 3.35 ERA in 49 games. He struggled with his command during Spring Training 2010 and, after being sent down to the Minors, struggled in April before being diagnosed with a torn ligament in his left elbow.