According to Jim Salisbury of CSN.com, one of the prospects heading to Houston in the Roy Oswalt trade is outfielder Anthony Gose.
Gose was a part of the Phillies 2008 draft in which they took a number of high-risk/high-reward players whose athleticism and tools were off-the-charts but were unpolished on the diamond. Gose, a 2nd round pick, has fit that profile precisely, showing flashes of brilliance on the field mixed in with moments of inexperience.
A brilliantly fast player, Gose has stolen 115 bases in 245 minor league games, however this year he's being caught at an alarming rate, notes Tyler Jett in Baseball America. For a player with Gose's speed, he does not show enough patience at the plate and has already struck out over 100 times in back-to-back seasons.
The third player in the deal may be Jonathan Villar, according to Ken Rosenthal. Villar is a shortstop prospect who may need to move off of the position soon, thanks in part to his 42 errors in 99 games there this season. Scouts believe in Villar's bat enough that he could be a big league regular, although if he has to move to a corner position, he may not have the power to be an impact player. He's much more of a line-drive hitter, and his fly-ball rates are way to high (career 27 %) for a player with such little power.

