The WhiteSox traded Carlos Quentin to the Padres for pitchers Simon Castro and Pedro Hernandez.
Quentin had a 3.2 WAR in 2011, but had an even 0 WAR over 2009-2010. The difference was his defense, as he had a 2.4 O-WAR in both 2010 and 2011. However, his D-WAR was -2.8 in 2009-2010, but .8 in 2011. He simply played much better in the field in 2011, with a horrible .959 fielding percentage in 2010, but a .994 fielding percentage in 2011. However, his range factor stayed about the same, and it is well below average. His career D-WAR is -.7, and he should still be considered a below average fielder. Offensively, Quentin has a .346 OBP, 116 OPS +, and 1.874 O4S. He has pretty monster power, with a .238 ISO, and a good Secondary Average of .344. In the end he is a pretty good offensive player, with 5.8 runs created per game and a .581 Offensive Winning Percentage. He homers 5% percent of the time, about double the average player, and is an above average walker and extra base hitter. However, due to a poor Pit/PA, he has a PPS that is not very good at 86.98.
Castro spent 2011 split between AAA and AA. His 8 career AAA starts in the PCL have been extremely poor, but at 36 innings, it doesn't make a whole lot of sense to judge him by that alone. As a starter n AA, 39 starts, he has a PE of -.343, which translates to about a 3.23 PE in the Majors. This of course would be horrible, so Castro can't be expected to contribute in 2012. He could, of course, improve and be part of the future, but there isn't a lot to suggest he will, and he doesn't offer any kind of immediate impact. He does keep the ball in the ballpark and has a good K/BB ratio.
Hernandez has just 4 AAA starts, and he struggled there as well, his 8 AA starts were better, but not a big enough sample size. Overall in his minor league career, he has split between both a starter and a reliever. In that time he has a PE of -.55, nothing impressive. However, he has had a FIP lower than his ERA in every stop he has made. Therefore, it makes some sense to cut him some slack and adjust his PE to about -.9. This probably projects to about a 2.4 PE, which isn't good as a starter or a reliever. He doesn't hardly walk anyone, and doesn't give up very many homers, so there is always that for the future, but it doesn't seem like Hernandez will have a 2012 impact.
Of course, the WhiteSox are in rebuilding mode, so as it is quite obvious the Padres win the trade for 2012, that really doesn't matter to Kenny Williams. With that said, I think that you would want to get a little bit more for the type of player Quentin is. There is the injury and defensive concerns with Quentin, but the Padres definitely need the bat.