CHICAGO -- The strained right oblique muscle that cost Adam Dunn two games in the Detroit series last weekend at Comerica Park knocked the slugger from the lineup for Friday's series opener against the Royals. Manager Robin Ventura said that Dunn aggravated the injury during Wednesday's victory over the Twins and it's not known how long he will be out of action.

"Just trying to care of it and make sure nothing gets worse," said Ventura of Dunn, who ranks second in the Majors behind Josh Hamilton with 38 homers. "It's just one of those that keeps coming back every once in a while.

"I'm hoping just today or tomorrow. You never know. It's just one of those, it's in a bad [spot]. I guess any time a hitter has it in his rib area, you can probably [re-injure] it every day."

Kevin Youkilis was also out of Friday's lineup. The veteran third baseman flew home to be with his wife, Julie, for the birth of their child. Ventura hopes to have Youkilis back Sunday. Jose Lopez started at third, Dewayne Wise in left field and Dayan Viciedo at designated hitter Friday to make up for the two absences.

Pierzynski says rumor without merit

CHICAGO -- A.J. Pierzynski has been one of the key forces behind the White Sox first-place standing in the American League Central, both behind the plate and with the bat.

And with 25 games remaining after Friday night's contest, Pierzynski certainly doesn't want to spend time talking about an Internet rumor concerning his connection to a positive test for performance-enhancing drugs. So, when asked about the topic, which took root Wednesday, the hard-working catcher simply made a brief statement.

"Well apparently, certain people in the media, they know who they are, I don't have to mention them by name, they just go ahead and run stories and talk about stories on their air without getting sources," Pierzynski said. "It's a shame because people that don't do anything, haven't done anything, can be targeted and you can say whatever you want on the Internet.

"That's the life we live and the world we live in and unfortunately it's happened to other people and this time it happened to be on me. It's over with now and hopefully people find something better. ... We can talk about the White Sox instead of something that is completely baseless."

Floyd encouraged by latest bullpen session

CHICAGO -- The White Sox starting rotation for next week against Detroit features Jose Quintana on Monday, Jake Peavy on Tuesday, Francisco Liriano on Wednesday and Chris Sale on Thursday in the rematch with Justin Verlander.

Gavin Floyd won't factor into the Detroit mix, but he's getting closer to a return. Floyd, who has been on the disabled list retroactive to Aug. 27 with a right elbow flexor strain, threw a bullpen during Thursday's off-day. He threw around 55 pitches in a long session, and while he is yet to throw any curveballs, he gave a thumbs-up to the sliders employed in the session.

"I was a little apprehensive because the last time I threw sliders was like every time I threw it, it bothered me," said Floyd, who also mixed in fastballs and changeups. "So it was nice to throw some sliders and have no pain.

"Very minimal soreness, ache. So it was good, better than I expected. We have one more bullpen Sunday to throw curveballs and I think that will be the final test as to how it feels and see how it reacts when I throw."

Floyd would like to return to the rotation as soon as he is healthy and believes he can do so without throwing any simulated games. The right-hander even thought the Detroit series was possible, although manager Robin Ventura was not as convinced.

"He's got to feel right to be able to do that," Ventura said. "Again, I don't like sending guys out there not feeling 100 percent. I don't want them going with any reservations when he's going out there. As soon as he's fit to do it, we'll look at where he best fits in."

"We'll see what happens Sunday," Floyd said. "I think the plan is to get me back there as soon as we can."

Third to first

• The White Sox expressed concern over the condition of Brandon McCarthy, the A's hurler and former White Sox pitcher, who was struck in the head by an Erick Aybar line drive Wednesday.

The A's announced on Thursday that McCarthy had surgery to alleviate pressure in his head Wednesday night after a CT scan revealed an epidural hemorrhage, brain contusion and skull fracture. The release said McCarthy was alert, awake and resting comfortably, although his condition still is considered life-threatening.

"He's a friend of mine," said White Sox catcher A.J. Pierzynski, who texted his concern to McCarthy. "You never want to see a guy get hurt. You never want to see someone hit in the head. It's a shame. I wish him a speedy recovery and I hope he gets back."

McCarthy was traded to Texas on Dec. 23, 2006, in exchange for John Danks, who was struck in the head by a Stephen Drew liner last season.

• According to Elias, Alex Rios' six RBIs in Wednesday's 6-2 win over the Twins matched the club record for RBIs in a game in which one player accounted for all the team's runs. Al Simmons (1933 vs. Detroit) and Roy Sievers (1961 vs. Detroit) previously accomplished the feat.

• The White Sox 36 comeback wins this season are tied with Pittsburgh for the fourth most in baseball. The Yankees, Reds and Brewers are tied for first with 38. The White Sox also have played 85 games decided by three runs or fewer, with a record of 22-16 in one-run games, 12-20 in two-run games and 9-7 in three-run contests.

• Friday marked the popular Halfway to St. Patrick's Day promotion at U.S. Cellular Field.

• The White Sox have homered in 12 of their last 13 home games, producing 25 homers, and 24 of their last 26 home games overall, producing 48 in total.