Can anyone offer a good explanation for this move?

Twins Sign Andrew Stevenson To Minor League Deal - MLB Trade Rumors

I suppose there's no harm in giving him a look-see. It's a no-risk contract, and if he's better than the likes of Contreras, LaMarre or Garlick we can keep him instead of them when cut-down day arrives.

13 minutes ago, Althebum82 said:

Can anyone offer a good explanation for this move?

Depth. Celestino getting hurt. Gordon banged up. Twins think he may be better than Contreras and want to find out. Someone is going on the IL and Larnach is starting the season with the Twins. He can play CF relatively well. All are good reasons to add minor league depth and give the guy a try on a minor league contract. 

Probably bad news for guys like Keirsey (who I like) and Prato.

3 minutes ago, FlyingFinn said:

Depth. Celestino getting hurt. Gordon banged up. Twins think he may be better than Contreras and want to find out. Someone is going on the IL and Larnach is starting the season with the Twins. He can play CF relatively well. All are good reasons to add minor league depth and give the guy a try on a minor league contract. 

Probably bad news for guys like Keirsey (who I like) and Prato.

Agreed, I think this move was primarily because Celestino is injured.  AAA depth is likely Contreras, Wallner, Garlick and Larnach if he gets squeezed out. So probably best to have one more guy that can play multiple outfield spots just in case.

There is not much outfield depth at AA to move up.  Keirsey probably starts there as it is probably the best place to jump start his bat.  It might stink a bit for Prato as he can play Left for sure but he should have plenty of chances in the infield as well.  Probably a good move to shore up depth.

The team really needed to shore up the left handed outfielder position. This one was a no brainer.

"However, he does have less than three years of MLB service time, giving the club the ability to retain him for future seasons via arbitration if he breaks out at the plate."

A crap shoot.

Not looking good for Ryan LaMarre.

Nothing wrong with signing a AAAA player to a minor league contract.  His resume looks like he's THIS close to being a productive major leaguer.  Maybe the coaching staff unlocks the one needed tweak to his game at the plate.  It's his first change of scenery.