Kalina came up with the great idea to do posts about the members of the Orioles 40 man roster that have yet to see Major League action with the Birds. Since we have seen a majority of those guys play at either Frederick and/or Bowie, I have autographs from most of them and can provide a little information about them.
Perez has been a member of the Orioles organization since signing as a minor league free agent before the 2005 season. He has pitched for Bluefield, Aberdeen, Delmarva, Frederick and Bowie over his five seasons in the system so far. He was originally a starter but was converted to a reliever in 2007 while with the Shorebirds and his career has taken off since then. He has had multiple dominating stretches which include pitching 25 consecutive scoreless innings at the end of '07 for the Shorebirds.
Before the '09 season he had a real chance to make the Orioles as the left-handed reliever but battled some injuries that prevented him from coming North with the O's. We have seen him pitch at both Frederick in 2008 and Bowie in 08 & 09. As you can see, he normally signs with his number 44 under his last name, but not always. If he makes the O's, it's unlikely he would wear that number since it's been unofficially retired in memory of Elrod Hendricks.
And here is a signed article from the Bowie Baysox gameday magazine last year that has some more information about him if you're interested.
I really hope that Willy can make the Orioles this season. The left-handed reliever spot isn't exactly locked down so if he has a good spring training he could be making his Birdland debut this April.