FORT MYERS, FLA. - Brendan Harris had signed a two-year contract and was guaranteed a spot as a backup infielder for the Twins to start the 2010 season. There was another job available and the candidates were Matt Tolbert and Alexi Casilla.

Tolbert had played third base for the Twins in the drive to catch Detroit late in 2009. It seemed that the only factor to favor Casilla was that he was out of options to the minor leagues.

The Twins were set in so many places that Tolbert or Casilla was a topic of regular inquiry for reporters. And then with two weeks left in Florida, manager Ron Gardenhire announced, "Casilla will be on the team."

It was anyone's guess if Gardenhire was rattled by a few Tolbert misadventures in the field, or if he had been told by the front office that it was not going to risk losing Casilla on waivers.

There has seemed to be a disconnect recently in the value placed on Casilla by the organization and in his performance.

He had a half-season of effective play at second base in 2008 and was handed the job in the spring of '09. He gave it up quickly with futile play, batting .202 in 80 big-league games.

Last season, Casilla spent seven weeks on the disabled list after having surgery on his right elbow. He came back in late July as the backup to Orlando Hudson at second base and J.J. Hardy at shortstop.

Casila played in 69 games with 152 at-bats. He batted .276.

It looked like the résumé of a backup, at best, and then Gardenhire started suggesting in the offseason that Casilla -- once a member in good standing of the manager's doghouse -- figured as a regular at second or shortstop in 2011.

Hardy and Hudson were gone. Tsuyoshi Nishioka, the batting champion in Japan, was signed on Dec. 18. And Saturday, Gardenhire said he had decided on his new middle of an infield: Casilla at shortstop and Nishioka at second.

Which brought up a question for the manager late Monday morning: "What did Casilla show last season that would cause a declaration that he's your shortstop?"

Gardenhire said: "He had to change, to listen, to prepare, to pay attention to every situation on the field, and that's what he did. And that started to bring out the talent again that we saw a few years ago [2008].

"You gotta remember that. He's always had talent. He can run. He has good hands and a shortstop's arm. When he's right at the plate, he can be a tough out. And what I like is that the same things we saw from him in the second half of last season, we're seeing this spring."

There you have it: Gardenhire's assurance that Casilla has been aware of the number of outs at all times this spring, and that's an improvement right there.

There was another question for the manager: How much of the decision to give Casilla another shot as a regular has been based on last summer's discovery that Target Field was a big yard where speed should play better than power?

"It's part of it, yeah," Gardenhire said. "One thing I didn't like last year, with our ballclub, was if we weren't getting extra-base hits, we couldn't do anything. We didn't have the speed to send runners, to take an extra base. We couldn't take advantage of the big gaps in our ballpark like we want to."

If Casilla kicks this opportunity to be a regular, as he did in 2009, the Twins could move Nishioka to shortstop -- but Gardenhire already has indicated that he prefers him at second.

Trevor Plouffe, 24, the No. 1 draft choice from back in 2004, likely would get a chance. Does Gardenhire see him as big-league ready as a shortstop?

"Plouffe's range is good enough, and he can hit," the manager said. "What he needs is consistency in the field. He gets careless with his arm slot and makes too many bad throws."

It would have been tough to figure even a year ago that the Twins would be looking at consistency as a factor that recommended Casilla over another candidate at shortstop.

Patrick Reusse can be heard noon-4 weekdays on 1500ESPN. preusse@startribune.com