FORT MYERS, FLA. – One June day in 2008, Twins manager Ron Gardenhire and pitching coach Rick Anderson headed for the Metrodome bullpen before a game to join a group of team officials watching some thin righthanded high school pitcher work out for them.

"He was a big tall kid winging it," Gardenhire said. "His mechanics were wacky and all that stuff. [But] we said right away, this is the kind of guy we want in the organization."

Gardenhire and Anderson have worked with all types of pitchers, but they are no different from other teams in desiring more power arms in the farm system. So when they laid their eyes on Michael Tonkin, they saw potential and told the club to do what it could to sign him.

So the Twins signed Tonkin, a 30th-round pick who was headed for college to Southern California, for $230,000. Now Tonkin, 23, is emerging as one of those coveted power arms, which would make the $230,000 a good investment.

In 44 games between Class A Beloit and Class A Fort Myers last year, Tonkin was 4-1 with a 2.08 ERA and 12 saves while averaging 12.6 strikeouts per nine innings. He also pitched for Peoria of the Arizona Fall League, going 1-0 with a 2.45 ERA with three walks and seven strikeouts in 10 games.

His fastball reaches about 95 miles per hour, but the development of a lethal slider has helped him rise up the organizational prospect rankings. Tonkin tinkered with a curveball and slider for several years before the breakthrough last season.

"The development of the slider last year was huge," Tonkin said. "I felt like I had hit a roadblock the years before that, but getting that slider down was definitely a difference-maker.

"It's still a work in progress, but it's much better than it was before."

The Twins were prepared to be patient with Tonkin. He has made 132 appearances in the minors, but 25 of those were starts. Last season was the first time he spent an entire season working out of the bullpen.

"As you know, we brought him to the Metrodome a few years ago just before he signed," Twins General Manager Terry Ryan said. "He had the body, had the arm action. He was athletic enough. He had velocity. He had a lot of life. I think it was just maturation both mentally and physically."

Tonkin, from Glendale, Calif., gladly signed with the Twins in 2008. He had slipped in the draft that year because teams were scared off by his college commitment. The other factor was that his brother-in-law, Jason Kubel, played for the Twins at the time. Kubel told the Twins that he was willing to sign for the right offer, and the Twins decided to bring him in for the workout.

So Tonkin decided to skip college to join the Twins. He's baby-faced but stands 6-7 and has filled out to 220 pounds.

He has made it look easy so far this spring, tossing four scoreless innings while giving up one hit and two walks with two strikeouts. He threw the ball well during an inning of work Friday against the Red Sox.

The Twins have started cutting players from camp, and Tonkin might not be around much longer as the club evaluates players who can make the big-league team. He is expected to open the season at Class AA New Britain, so with the right breaks, he could debut sometime this year.

If he continues to overpower hitters the way he did last season, there will be at least one person with the Twins who will lead the charge to have him called up — one of the people who watched him work out in Dome in 2008.

"I love him," Gardenhire said. "He throws the heck out of the ball and lets it fly.

"They have done a really nice job with him through the minor league system, getting his mechanics cleaned up, and he is one of our young bucks. He can be a big factor in this organization."