Mike Trout, Outfielder, Los Angeles Angels
The reason I don't have Mike Trout as a candidate, is he is trying to earn a starting gig in the outfield. With Vernon Wells, Peter Bourjos, Torii Hunter and Bobby Abreu already up at the major-league level, there is no clear spot for Trout in the outfield. If one of those players are traded (in particular Bourjos), then Trout would find his way on to my list.
Devin Mesoraco, Catcher, Cincinnati Reds
Mesoracro is currently slated as the backup catcher behind Ryan Hanigan. As he will likely be splitting time with Hanigan for most of the season, he did not qualify ahead of the others on my list.
Yu Darvish, Starting Pitcher, Texas Rangers
I am not personally sold on Darvish. I do not know if his abilities will translate to success over here in MLB, and I like the other candidates from the AL that I listed better.
Yoenis Cespedes, Outfielder, Oakland A's
Cespedes may not be reaching the majors this season, as he may be sent to the minors to adjust to pitching here in the USA. If all goes well down there, he may fight for a later spot on my list.