CLEARWATER, Fla. - Tommy Joseph was on a fast track to the major leagues, or, as the 23-year-old Arizonan puts it, he was "scootin'."

The San Francisco Giants twice invited him to big-league spring training before he was even of legal drinking age. He was only 21 when he took his first triple-A at-bat with the Phillies organization.

Thirty-one months after becoming the centerpiece of the Phillies' return in the Hunter Pence trade, Joseph is just trying to stay on the field. If he manages to remain healthy, the rest will take care of itself, he contends.

Health has proven the biggest hindrance to his development.

His last two seasons were more or less a wash, one lost to persistent concussion issues, the other to a freak wrist injury. It was July 31, 2012, when the Pence trade instantly made Joseph the Phillies' top position-player prospect. He no longer appears on prospect lists from publications such as Baseball America.

But in spring training, without health restrictions, Joseph doesn't see why he can't recapture the promise that not long ago made him one of baseball's top catching prospects.

"It's not like I got worse," he said. "I haven't declined. I just haven't played."

In his fifth major-league camp, Joseph readies for a crucial season. The Phillies would love to see him garner 500 or so minor-league at-bats so they can find out how he factors into their future. If he makes it through the next four weeks without issue, Joseph should again get a chance to play every day in double A or triple A.

"All of the things that you hope you get, we see it when we've got him on the field," said Joe Jordan, the Phillies' director of player development. "Hopefully he's blessed with a year where he can just play and where we can get a really good idea on what we have.

"We just haven't been able to get that sustained look yet."

Joseph can't pinpoint the number of concussions he's sustained. It's difficult to discern between those diagnosed and others that amounted to, more or less, scares. He estimated he's had three or four full-blown concussions.

The first, he knows, came during his first professional season, 2010, with the Giants' single-A affiliate in Augusta, Ga. Another happened with double-A Richmond in 2012.

The "big blow," though, occurred the following year, just 21 games into his first triple-A season at Lehigh Valley, when Joseph absorbed a foul tip into his catcher's mask and "instantly felt terrible." After managing a base hit the next half-inning and advancing on a walk, a double had him running two bases to score.

"It was like my brain was in a tornado," he said.

Joseph was replaced to start the next inning, his season essentially over. He made three appearances for double-A Reading that July before he was shut down.

The symptoms cleared in time for him to make up at-bats that winter in the Dominican Republic, and he started last season back in Reading. It was smooth sailing until a game in New Hampshire, when another foul tip to the mask sparked a scare that left him at a crossroads.

Ernie Whitt, the Phillies' minor-league catching coordinator, attended the game that night. He and Joseph sat in the dugout after the game, the catcher feeling lost as he considered the dire possibility his days behind the plate were over. They stepped into Reading manager Dusty Wathan's office and shut the door.

Joseph broke down.

"I lost it," he said. "I thought that was it."

That, Joseph said, was the low point. Looking back, he considers it an overreaction based, understandably, on his experiences of the previous year. A visit to renowned concussion expert Micky Collins in Pittsburgh reassured Joseph everything was fine. Stop worrying, Collins told him.

Joseph's concern over the concussion scare had dissipated when, two weeks later, a Jesse Biddle fastball hit the catcher's glove hand at an odd angle and blew open the tissue and fascia around a tendon in his left wrist.

A numbing sensation came over Joseph. Biddle, the former first-round draft pick from Germantown Friends, didn't learn anything was wrong until the inning's end. In the dugout, Joseph was asked to squeeze a trainer's wrist. Biddle remembers hearing a pop.

In an effort to salvage his season, Joseph opted against surgery. Five home runs, 19 RBIs, and an .896 OPS in his first 78 at-bats of 2014 were his best stretch in the Phillies organization.

But one day in July while taking batting practice in Clearwater he decided he had enough. The rehab wasn't progressing quickly enough. The Phillies shut him down, and he underwent surgery Aug. 5.

After two months in arm casts, Joseph rehabbed at the Andrews Institute, not too far from Destin, Fla., where he and his fiancee, Ali Nordlander, own a house. (She is a labor and delivery nurse in the Air Force and stationed at the base there.)

"I think he kind of felt like he had the world at his fingertips, being traded and he was a top prospect," Nordlander said, "and then all of a sudden it was like he hit this roadblock and couldn't get out of this roadblock, and it was injury after injury."

Joseph was cleared for baseball activities just after the first of this year and has been a full participant in spring training. While still working to shed some of the weight gained during all the inactivity because of the injuries, he said he feels great. Last Sunday, he lifted a single into left field during the Phillies' first exhibition game.

"You just forget how awesome that feeling is, getting a hit and being out there on a ball field and running around," he said afterward. Three days later, he started against the New York Yankees in Tampa.

"Hi, Tommy," Alex Rodriguez said as he stepped into the batter's box for the first time in almost 18 months.

Without any more roadblocks, Joseph has no reason to think he can't get his career back on track. His new wrist has held up great while swinging the bat. Pitchers still laud his ability to handle a staff.

"If we can get a season of good health, we feel like this guy fits in our future," said Jordan, the Phillies' farm director. "We've got to keep him healthy and let him play."

A recurrence of the concussion issues could lead to a move to first base, but this spring that seems far from Joseph's mind. He is without limitations as he prepares for the season. He recently started wearing a thicker, more durable "super helmet" as a precaution.

Phils catching coordinator Whitt, a sounding board for Joseph throughout a struggle-filled couple of years, said: "Any time I see Tommy with catching equipment on I think it's a great day."

The former longtime major-league catcher hopes Joseph reaches a point he no longer thinks about concussions.

Every symptom-free occurrence of a ball or bat clashing with Joseph's mask reduces any worries that might linger. When a foul tip came Joseph's way in last Sunday's exhibition, Whitt watched closely from the bullpen, his eyes fixed on the catcher through his inning-ending walk back to the dugout. All was well.

This season, the Phillies hope, is when they can finally evaluate Tommy Joseph. The once-touted prospect hopes that incites a belated return to the fast track.