No, Pete Carroll did not name a starting quarterback for Saturday’s game against Arizona. But after John David Booty (fractured finger) sat out of practice for the third consecutive day, even he seemed to expect Mark Sanchez to start. And Booty isn’t the only one who is likely to be out on Saturday. We examine the latest injury developments in our daily coverage roundup.

• USC’s offensive line depth–such as it was–took an even greater turn for the worse on Wednesday with the word that backups Charles Brown and Thomas Herring (each with ankle sprains suffered in practice this week) were extremely doubtful for the Arizona game. With Kris O’Dowd (knee), Chilo Rachal (knee), and Matt Spanos (lacerated finger) continuing to sit out, that left Wednesday’s first unit consisting of Jeff Byers at center, Sam Baker and Drew Radovich at tackle, and Alatini Malu and Zack Heberer at guard. And the options behind them aren’t too promising. The only remaining offensive linemen are Alex Parsons (who only recently moved to offense from the defensive line), Michael Reardon (who coaches had planned on redshirting this season) and Butch Lewis (who is still suffering the effects of an ankle sprain). Note that Spanos, at least, is still likely to play on Saturday, although coaches may still start Byers at center, since he has had a chance to work with new QB Sanchez this week while Spanos has not.
• Booty’s finger experienced additional swelling after the quarterback tried throwing prior to Tuesday’s practice, and he did not engage in any activity on Wednesday. Carroll seemed open to sitting Booty on Saturday even if he shows some improvement in the next few days in order to ensure that he will be at 100% for future games. Coaches opened up the offense a tiny bit more for Sanchez on Wednesday, and he responded well, at one point completing a 50-yard bomb to Ronald Johnson.
• RB Stafon Johnson (foot) did not return to practice, but he has resumed jogging, and estimated that he was at 80%, and will play Saturday if he can get back to 90% by the end of the week. Carroll indicated that Hershel Dennis will be the primary backup behind starting tailback Chauncey Washington, with Desmond Reed at third-string. In other words, don’t expect to see Allen Bradford or Joe McKnight much this week. McKnight fumbled during drills on Wednesday.
• In the good news department, LB Thomas Williams (ankle) was much improved on Wednesday and will definitely play against Arizona. He even has a chance at starting again, although Clay Matthews is more likely.
• WR Vidal Hazelton practiced with the first-team offense, ahead of usual starter David Ausberry.
• CB Vincent Joseph appears to be mounting a challenge to Mozique McCurtis for the primary nickelback position.
• LB Chris Galippo’s back surgery is scheduled for Friday.
• FB Stanley Havili told Scott Wolf that the Trojans were not their normal selves prior to the Stanford game: “It seemed like last week, intensity dropped off and the attitude of playing for USC dropped off.” In case you are wondering, he added that practice has been much more intense this week.

Insider: Where have all the linemen gone? (Rivals, $)
Sanchez seems almost certain to start (LA Times)
USC QB decision still unsettled (OC Register)
USC’s Havili says Stanford loss followed lethargic week of practice (Daily News)
All signs point to Sanchez as USC’s starter (Daily Trojan)