LAKELAND, Fla. -- Tigers utility man Don Kelly had been joking with reliever Joel Zumaya that he wanted to get into the batter's box against him this spring, wanted to take his swings against him. He might have even gotten Zumaya pumped up a little.

On Wednesday, as Zumaya warmed up for his first meeting with actual hitters during batting practice, Kelly was lucky. He was hitting somewhere else. It was up to Brent Dlugach, Gustavo Nunez, Audy Ciriaco and others to take their first swings of the spring against Zumaya and Jose Valverde.

"Always fun," Dlugach said with a hint of tragic sarcasm.

Manager Jim Leyland agreed.

"It wasn't too much fun for those hitters," Leyland said.

They weren't lining up to face Zumaya, but there were plenty in Joker Marchant Stadium waiting to watch him, from Leyland to team president/general manager Dave Dombrowski, Valverde to ace Justin Verlander, Daniel Schlereth to his dad Mark, the former NFL lineman. A good number of fans were in the stands, after rains waterlogged the back fields of the Tigertown complex.

What they all saw didn't disappoint, and it did nothing to diminish the notion that Zumaya is back to his old stuff.

Leyland tries to be cautious when it comes to evaluating pitchers in Spring Training workouts. He even sometimes wishes he didn't watch pitchers throw bullpen sessions so that he wouldn't get too excited. But so far, he's having a hard time containing his enthusiasm over Zumaya.

"The ball's just flying out of his hand," Leyland said. "I mean, I watched him throw the other day and I remarked to one of the coaches, 'You know, how does a human being hit that?' That blows my mind."

They didn't hit much of it Wednesday, but that's to be expected. Live batting practice should probably be called live pitching practice, because pitchers are always ahead of hitters at this point in camp. In Zumaya's case, it's even moreso, because it was his 10th session off a mound since he came to Tigertown in January. Regardless, it's tough to ask inexperienced players such as Dlugach and Nunez to hit Zumaya.

Zumaya gets that, which is why he mixed in a fair number of breaking balls along with those fastballs Wednesday. If he can spot a first-pitch breaking ball here and there, he said, he can keep hitters a little more honest.

But Zumaya is also honest with his situation. Getting back to full health is a gift for him, but he has to stay healthy.

"If I don't keep the shoulder working, I'm going to be on the shelf," Zumaya said. "I do therapy three times a week at home. It's just to get that shoulder as strong as I can. Basically, my trainer and our trainers told me that if I don't keep this shoulder up, it's going to be my fault, and I'll end up on the DL. If I keep it up, I'll be healthy all year."

That was a problem last year, but Zumaya admitted Wednesday that he never was completely healthy. He had a stress fracture in his shoulder that included a bone shard in the shoulder capsule, but he was told by doctors that he could rehab it without surgery and pitch through it. NFL quarterbacks have been able to play through it.

The problem is that quarterbacks were pretty much the only case studies on which Zumaya could rely. The injury is extremely rare in baseball, much like the more devastating shoulder injury Zumaya suffered after the 2007 season.

"You don't know," Leyland said, "because no pitcher has ever had this exact injury before."

As it turned out, nobody knew how much Zumaya was hurting last year until he couldn't pitch anymore. He was never really healthy once he returned to action, he now admits. It was just a matter of how much his shoulder bothered him on a given day. He kept thinking it was bound to get better as he kept throwing.

"It bothered me all of last year," Zumaya said. "I kept my mouth shut. Simple as that. I tried to do as much as I could to help this team. And it's probably my fault that I did it, but you know, I'm a competitor. I don't want to be sitting on the bench and watching my teammates go out there and battle it off.

"It bothered me a lot. So that's why I made the decision to get it taken out. It was probably the best thing I could've done."

Zumaya didn't undergo the operation, though, until he could no longer lift his right arm. His shoulder grew more and more sore with each week, but Zumaya alleviated the pain with cortisone shots. That July evening at Yankee Stadium, when he struggled through 36 pitches, was the point where he couldn't deal with it anymore.

"A lot of people ask, 'How was he hurt throwing 98 miles an hour?' That was all adrenaline," he said. "I was trying to get out of the inning. I'm not gonna lie. Right when he pulled me out [that night], I went right underneath [the stadium], and tears were coming out of my eyes, because I couldn't even lift [my arm] up."

This time, Zumaya insists, he's healthy. He is no longer a rehabbing pitcher, and his pitches so far back it up.

"I'm holding my breath," Leyland said, "because that stuff is nasty."