He pitched reasonably well with the Sidewinders at Triple A Tuscon, converting all 3 save chances and striking out more than a batter per inning. If I remember correctly he had an ERA around 3. I doubt that he closes unless Julio flops or unless the D'backs are out of it near the end of the season. Even then Pena might get some chances. If effective, he might be good for holds, K's or K/9 if you are in a really deep league, but not much else.
"Trying to hit him was like trying to drink coffee with a fork." - Willie Stargell on Sandy Koufax