FORT MYERS, FLA. - Deolis Guerra is all the Twins have left to show from the 2008 Johan Santana trade, and last year, it looked as if Guerra might disappear from the organization, too.

After 10 starts for Class AA New Britain, Guerra had a 9.00 ERA and an opponents' batting average of .357. The Twins didn't want to give up on the 22-year-old righthander, but something had to change.

They moved him to the bullpen and discovered a new pitcher.

"I think it was a great move for me," Guerra said. "Coming out of the bullpen makes me more focused every day. I think that was the key."

In 27 relief appearances for the Rock Cats, Guerra posted a 2.77 ERA and held opponents to a .191 average. The Twins added him to their 40-man roster at season's end and believe he can still become a decent big-league reliever, perhaps even later this year.

Guerra was one of the first cuts the Twins made this year from their spring training roster, after he'd allowed five earned runs in three innings, but that's not a reflection of his organizational standing. Baseball America recently ranked him as the team's No. 15 prospect.

He's expected to be one of the relievers knocking on the door this year at Class AAA Rochester.

"I don't know if he's a guy that maybe tries to pace himself when he starts, but when he knows he's in for short shots, he really seems to get after it," said Eric Rasmussen, the team's minor-league pitching coordinator. "So maybe that's his niche."

Guerra arrived from the Mets with considerable hype. In 2007, at age 18, he was in the All-Star Futures Game, and his fastball reached 95 miles per hour. But scouts believe the Mets stunted Guerra's development by rushing him to Class A St. Lucie that year.

"He was in the [Class A] Florida State League when he was about 18 years old, which is really silly," Rasmussen said. "Because then you're over your head, and you've got to repeat the league over and over. Unless he's a sure thing, but how rare is that?"

Guerra's best pitch has been his changeup. His fastball is straight and barely touched 90 mph as a starter, but as a reliever, it consistently hits 91 mph.

"His curveball is better now, too," Rasmussen said. "He's really worked on that. And he's also slimmed down. He started getting in shape last year and taken it to heart."

Guerra's development could salvage a disappointing trade for the Twins. Santana, who turned 33 this week, was a two-time Cy Young Award winner, but he was one year from free agency and controlled the process because he preferred to eventually sign with a big-market team on the East Coast.

An expected bidding war between the Yankees and Red Sox never materialized, and the Twins settled for four prospects from a thin Mets system: Outfielder Carlos Gomez, starting pitchers Philip Humber and Kevin Mulvey and Guerra.

The Twins traded Gomez to Milwaukee for shortstop J.J. Hardy and, using the waiver wire, sent Mulvey to the Diamondbacks for reliever Jon Rauch. But Hardy's with the Orioles now, Rauch jumped to the Blue Jays and now the Mets, and Humber's with the White Sox.

"I think it was a real good thing for me being traded for a guy like Johan," Guerra said. "He's one of the best. I don't think it put more pressure on me. I just try to control what I can control."

In four years as a Twins minor leaguer, Guerra has posted a 5.55 ERA, and he's only made five appearances above Class AA. He realizes Twins fans are probably growing impatient.

"I feel ready [for the big leagues]," he said. "It been a long process, and I'm working hard, trying to prove myself. The Twins have the last word, you know, but I'm ready for whatever they want me to do."