Mastroianni is competing for that spot along with prospects Aaron Hicks and Joe Benson, but he has a leg up. Hicks is yet to reach Triple-A Rochester, and Benson is coming off an injury-plagued season in the Minors after getting his first taste of the big leagues as a September 2011 callup.
"Obviously, it's an unbelievable opportunity, and I won't take it lightly, but my goal is to prepare just like I would for any season," Mastroianni said. "I'm going to try to prove to them I can handle that role, and take over that job this year. Right now in Spring Training, I'm just trying to prepare for April 1."
Mastroianni got in extra work this offseason, playing in 29 games for Aguilas de Zulia in the Venezuelan Winter League, where he hit .256 with a .381 on-base percentage and eight stolen bases. It came after he hit .252/.328/.350 with 21 stolen bases in 77 games with the Twins.
"The main goal was to get down there and see some pitching, because last year I got fewer at-bats than I usually do," Mastroianni said. "Last year, in a utility role, I had a little less at-bats."
Twins manager Ron Gardenhire said he's excited to see what Mastroianni can do now that he has a chance to play every day, since Denard Span and Ben Revere were traded this offseason.
"He brings that excitement to the game," Gardenhire said. "Anything can happen. He can steal bases. He's game on. He likes to get dirty and run around and dive all over the place. If you want somebody to amp it up a little bit, he can do that. He gets everybody excited with the way he runs the bases and steals. So I like that about him."