NASHVILLE - The trades of Denard Span and Ben Revere leave the Twins with uncertainty at a position that's usually secure: center field.

Since 1999, the Twins have started only three different players who were considered regulars in center: Torii Hunter, Carlos Gomez and Denard Span. Even if Gomez's at-bats drove everyone mad, he was gifted defensively. Standards have been established here.

Revere, with his acrobatics, showed he was more than capable when filling in for Span and it was a no-brainer that he would take over when Span was traded to Washington last week.

But what do the Twins do now?

Twins General Manager Terry Ryan said on Thursday that Darin Mastroianni, a reserve last season, and prospects Joe Benson and Aaron Hicks will get a chance to win the job in spring training. But they will consider bringing in additional help.

"They are all center fielders," Ryan said, "and the winter has not concluded yet, so we will look to see if we need to fortify it. We still have three in-house options for these guys to earn whatever playing time, and if we see another scenario where we can go out and get another one, we probably could."

Mastroianni, 27, batted .252 in 77 games last season, his longest stretch in the majors. He's one of the fastest runners in the organization and capable as a fourth outfielder. Can he handle more of a workload?

Benson, 24, was a second-round pick in 2006 who played in 21 games for the Twins in 2011. Last year was a disaster as he battled injures and never found a groove at the plate, skidding to a .202 batting average with six home runs and 36 RBI in 76 games. He has to make more contact and harness his power potential.

Hicks, 23, was a first-round pick in 2008 and was expected to get his shot in 2014 or later. He batted .286 with 13 homers and 61 RBI in 129 games at Class AA New Britain. The switch-hitting Hicks has a good batting eye and is considered one of the Twins' top prospects as well as the center fielder of the future. Who knew the future could be next April?

"I don't think there is any question that all three could handle the defensive side of the game," Ryan said. "They all can field. They are very athletic. They all can throw. They all can run. They all have the type of range they need.

"Now whether offensively they can handle the responsibility, that's the question."