The last time the Twins had a competition for center field was when Torii Hunter left. There were three young players who came to spring training hoping to win the position. Carlos Gomez came from the Mets as part of the Johan Santana trade. Jason Pridie came from Tampa Bay as part of the Matt Garza tradeDenard Span had been heir apparent, but was considered by some to be a failed first round prospect. Gomez won that competition. Pridie never amounted to much. And Span eventually emerged as the Twins regular center fielder with Gomez traded to the Brewers.
This year there are three candidates for center field after the Twins traded away not only Denard Span, but his apparent successor Ben Revere. Aaron Hicks is the heir apparent. He is a former first round choice who had a decent year at AA. Darin Mastroianni was the Twins fourth outfielder in 2012 and impressed the Twins with his base running and defense. Joe Benson struggled last year even after being demoted to AA, but in the past he has shown impressive power in the minor leagues. Terry Ryan has said all three are natural center fielders with the arms and range to play there. The question for each is whether they can hit enough.
Its doubtful the Twins would have made those trades if they weren't fairly confident that they have someone to step in to the center field spot. I think Mastroianni is the guy who gave them that confidence. He plays good defense, he can run the bases and he is not completely lost at the plate.
Aaron Hicks is the guy the Twins are hoping will take the position, if not in spring training then sometime soon. Hicks brings above average range and arm to center field. Currently he is more a table setter offensively with good on base and baserunning skills. But he could easily develop Torii Hunter power in the future.
Joe Benson is a guy with great athletic skills. But those don't always translate to great baseball skills. He has showed he can hit for prodigious power, but whether he will hit often enough is a big question mark. Even against minor league pitching he was striking out 25% of the time. He also walked a lot. You can call that patience, but his success may come from waiting for minor league pitchers to get behind in the count and serve him a fat pitch he can hit over the wall. That won't work in the big leagues. Benson has the most to prove of the three candidates.
There are two non-roster players who can also play center field, CleteThomas and Brandon Boggs. They are not really candidates for the starting job. But they could win a job as fourth outfielder if the Twins start the season with Mastroianni in center field or someone gets hurt.