As Bryz noted earlier this morning, the outfield has been decimated by injuries and a lack of production from, more or less, Day One of the 2014 season. Oswaldo Arcia (last played April 4) and Josh Willingham (April 6) are your first and second examples of that very issue. But the good news is that both players are moving in the right direction.
Arcia has now appeared in 12 games for the Red Wings, and last night hit the first home run of his rehab stint in Triple-A. He's aggressive as always, but in 39 at-bats is currently hitting .308/.349/.487. A timeline on his return to the Twins hasn't been announced, and his return was initially pushed back due to continued inflammation in his wrist, but as long as he continues to play in Triple-A he's going to be in the discussion for a return to Minnesota.
Willingham, on the other hand, has been taking batting practice in Minnesota and "was whacking it pretty good." He'll continue to take batting practice over the next couple of days, but will soon be sent to Rochester for an extended rehab stint.
It's feasible that Arcia gets his recall when Willingham is ready to take a roster spot in Rochester, but as for now the only thing we can really say is that both guys are moving in the right direction. Arcia seems healthy after the wrist inflammation, having played in four of the Red Wings' last five games, and Willingham is days from playing in live games again.