GLENDALE, Ariz. -- Although Simon Castro, Scott Snodgress, Erik Johnson and Nestor Molina won't be part of the White Sox rotation at the outset of the 2013 season, they will be valued Minor League starters. With that in mind, they White Sox are keeping this quartet on a work schedule of every five days.

"Then when we hand them off to our Minor League people, it won't be going from one inning and now we have to get him to six," White Sox pitching coach Don Cooper said. "We'll hand off the baton to those guys, and right now they are in a good spot to where when we make cuts and get there, it's going to be an easier transition to go and get ready for their season.

"I want to give them everything they can get out of Spring Training," Cooper said.

Johnson (No. 3), Snodgress (No. 6), Molina (No. 10) and Castro (No. 16) all rank among the White Sox top prospects.

Castro made his second impressive Cactus League outing during Monday's 6-2 victory over the Giants. The right-hander worked the sixth and seventh, striking out five, while yielding just one hit. In five spring innings, Castro has yielded two hits and fanned eight.

"Stuff is good, changing speeds. Velocity is good. Aggressive throwing strikes, all of the things we wanted anybody to do," Cooper said. "He's thrown as good as we've seen him throw."

"He's more polished and just a better idea of what he's doing out there and more control," White Sox manager Robin Ventura said. "I think it just comes with maturity."

Infield shift gives Dunn fits, takes away hits

GLENDALE, Ariz. -- The defensive shift employed by opposing teams against Adam Dunn certainly wasn't invented for the White Sox slugger.

But it has cost him nonetheless.

With the first baseman, second baseman and shortstop all stationed between the first- and second-base bags, Dunn can rip a ball to right only to have the shot grabbed in short right field for an out. This scenario played out last week in a Cactus League contest.

It's frustrating for the big man who has hit the ball out of reach from fielders 406 times in his career. There's also not much he can do about it.

"I know people look at it and ask, 'Why doesn't he hit the ball over there [the opposite way]?' And you know, there's two reasons," Dunn said. "One is the way they are pitching me. It's really hard to, when the ball is diving down at your back foot, to hit the ball to third base.

"Two is where I stand on the plate. I'm on the plate probably a little more than I should. But that's where I've always felt comfortable. A pitch that's away that most people would hit the other way, that seems to be right down the middle to middle-away to me.

"That's a ball that I'll pull nine times out of 10," Dunn said. "It's something that has taken away a lot of hits in my career, but I don't know what else to do."

Dunn bounced back in 2012 with 41 homers and 96 RBIs, but he also batted .204. If you add 15 hits taken away by the shift, though, his average jumps to .232 and closer to his career .240 number.

Calling Dunn a pure pull hitter would be inaccurate, as he had 19 hits from straightaway center to left at U.S. Cellular Field in 2012. He is resigned to the fact that certain balls pulled to right will send him on a right turn back to the dugout, instead of rounding the bag to the left for a hit.

"All I try to do is hit the ball hard and it's going to go where it goes," Dunn said. "I was talking to [Conor] Gillaspie about that today. Where they pitch me most of the time, if I hit a ball good, it's going to go that way.

"I'm not going to sit there and try. It's really hard to hit a pitch that is coming down and in to you to third base. You know what I mean? It's kind of hard to do. It takes a lot of hits away from me. It is what it is."

Thornton eager to work out kinks in spring debut

GLENDALE, Ariz. -- Going against Team USA in an exhibition game Tuesday will have a slightly different feel than past Cactus League appearances for veteran White Sox reliever Matt Thornton.

It's still just part of the preparatory process for the hard-throwing left-hander.

"I'm not worried about the opponents right now," Thornton said. "I'm going to go out there and locate my fastball on both sides of the plate, mix in offspeed stuff a couple of times and get the first one out of the way, honestly.

"For me, it's about getting that first game, getting that good soreness out. Then, coming back for the next game and building off of it, building forward."

Thornton acknowledged that he'll have to make some good pitches in his one inning for hitters who have played a lot already and are dialed up and ready for World Baseball Classic competition. He missed one live batting-practice session this spring due to triceps soreness but never fell off schedule for his Tuesday appearance.

Prospect Barnum out six weeks after hand surgery

GLENDALE, Ariz. -- Keon Barnum, the White Sox sandwich pick (48th overall) in the 2012 First-Year Player Draft, had the hamate bone removed in his right hand during a surgical procedure Monday. The expected recovery period is six weeks.

The 6-foot-5, 245-pound first baseman sustained the injury last week, after the 20-year-old was limited to 13 games at advanced Rookie League Bristol last year and didn't play from June 24 to Aug. 3 and from Aug. 13 through the end of the season because of a shoulder problem.

Barnum, who is rated by MLB.com as the organization's seventh-best prospect, went 0-for-3 in his first pro game last year and then homered in his next three games and went 7-for-12 with seven RBIs.

Third to first

• Jeff Keppinger started at third base in Monday's 6-2 win over the Giants, marking his second start this spring defensively.

"Again, we were just trying to get him to swing the bat early, we weren't necessarily worried about [arm strength]," White Sox manager Robin Ventura said. "He looks fine. He looks comfortable over there."

• Zach Stewart threw two scoreless innings and struck out three in the White Sox 4-1 victory over the Padres during a morning "B" game.

• Ken "Hawk" Harrelson, the White Sox television play-by-play man in his 29th season, made his debut Spring Training appearance sporting a Chicago Blackhawks cap.