MIAMI, FEB. 26 -- A week after he was scheduled to report to the Baltimore Orioles, Jose Mesa walked into Miami Stadium this morning, put on his uniform and began spring training.

It wasn't what he had planned, not with a chance to make the major leagues. Not with a chance to follow six years of bus rides in the bushes for a shot at chartered jets and $49.50 per day meal money. Not with an opportunity to eat his supper in Toronto and Seattle instead of Kinston and Bradenton.

"I wanted to be here early," he said. "That was my plan, and I've spent the last week waiting for my visa. Now, I have to catch up."

The Orioles were as eager to see him as he was to arrive. He brings a 96-mph fastball to an organization woefully short of power pitchers, and he's one of the reasons the Orioles believe they have the pitching depth to get them back into contention sometime in the early '90s.

They're especially enthusiastic about the three young Latins: Mesa and Oswald Peraza, who were picked up from the Toronto Blue Jays for Mike Flanagan, and Jose Bautista, who was drafted from the New York Mets this winter. They still think last year's rookies -- Eric Bell, Jeff Ballard and John Habyan -- may make it, and they're excited about the draft picks of 1987 -- Chris Myers, Anthony Telford and Pete Harnisch.

"We've got quite a few pitchers in the system who weren't here a year ago," General Manager Roland Hemond said. "You can't help but be excited about that."

None of them is more impressive than Mesa, 21, who had not pitched above Class AA until the Orioles, with nothing to lose, threw him into their rotation last September. He went 1-3 with a 6.03 ERA, but, for a team used to throwing change-ups and breaking stuff, his high hard one was a breath of fresh air.

"He's one of the hardest pitchers I've ever worked with," catcher Terry Kennedy said. "It's not just that he had good velocity, his ball had so much movement. With a young guy you can never tell, but all the pieces are there. His problem was that he made bad pitches, then got mad after the fact. He'd make a bad pitch, one that cost him three or four runs, then he'd bear down and blow people away."

Manager Cal Ripken Sr. put it another way: "Do you like Roger Clemens? They pitched against each other last year, and Mesa threw just as hard {96 mph}. Now, the difference was consistency. Clemens threw harder more consistently. Mesa made some mistakes, but young guys are going to do that. You have to like anyone who throws the ball as hard as he throws it."

For his part, Mesa liked his taste of the big leagues, and while he was erratic, winning only in an 8 2/3-inning performance against Detroit, he talks confidently.

"I enjoyed it," he said. "I wasn't intimidated or anything. I went out everytime thinking I could win."

Even at 21, he has been around too long to be an overnight success. He was signed by Toronto superscout Epy Guerrero at age 16, and during his time in the Blue Jays' organization never got above AA.

His problem in obtaining a visa is one of several faced by major league teams signing Caribbean talent. Major league baseball is given a number of work visas -- about 450, although officials won't reveal the exact number -- to be distributed among the 26 teams.

The problem with Mesa's visa apparently was that when it was approved the Orioles sent the notice to the U.S. consulate in the Dominican Republic by mail instead of cable. But Montreal, Toronto and Atlanta had similar problems, and Mesa said his flight to Miami Thursday had six other professional baseball players on it.

The Orioles had other players coming from the Dominican Republic, and they all arrived on time.

"I picked up my visa yesterday in Santo Domingo," Mesa said, "then I had to drive 2 1/2 hours back home to pick up my luggage. I was getting frustrated, but there's nothing you can do about it."

Orioles Notes: First baseman Eddie Murray also reported to spring training today and gave reporters his first "no comment" of the new season . . . Third baseman Ray Knight didn't arrive in time for today's workout . . . The news on reliever Don Aase continues to be good. He threw 10 minutes of batting practice today, and pitching coach Herm Starrette said, "If you didn't know he'd been hurt, you couldn't tell it. Really, his sore back is probably more of a problem now than the shoulder. The real test will come when he throws in a game. We'll see how quickly he bounces back."