NCAA Football Rankings 2011: 3 Top 25 Teams Who Will Be on Upset Alert in Week 4

Following the release of the AP Top 25 poll for Week 4 it's time to look ahead to next weekend to determine which teams will receive a scare from an unranked team. Here are three teams that will be on upset alert next weekend.

No. 13 South Carolina Gamecocks

South Carolina has yet to secure a blowout victory, but have survived all three of their games so far. The Gamecocks led East Carolina by just four midway through the third quarter before pulling away and defeated Georgia and Navy by a combined six points.

Next up for South Carolina is fellow SEC undefeated Vanderbilt. The Commodores have picked up back-to-back impressive wins over Connecticut and Ole Miss thanks to the dynamic running back duo of Zac Stacy and Jerron Seymour.

The Gamecocks have allowed more than 180 yards per game on the ground and will have their hands full with Vanderbilt. They have narrowed escaped on three occasions already in 2011, but if they don't improve that run defense this week, that run of good luck will end.

No. 23 USC Trojans

Props to Lane Kiffin and the USC athletic department for scheduling a cupcake-free schedule in 2011. The Trojans have already knocked off Minnesota, Utah and Syracuse and still have a bunch of tough games left to play.

They enter enemy territory for the first time this week to take on Arizona State. The Sun Devils had joined the AP Top 25 before losing on the road to Illinois due to an off game from Brock Osweiler. Those are rare for Osweiler and you can expect him to bounce back against USC.

In what is sure to be a shootout between two of the nation's most prolific passers, Matt Barkley will need to find holes in a Sun Devils' secondary that is giving up only 200 yards per game. Unless Osweiler struggles again, the Trojans will be in serious trouble.

No. 25 Georgia Tech Yellow Jackets

Georgia Tech has been running wild over opponents in 2011 to the tune of nearly 430 rushing yards and 60 points per game. Against Kansas, the option offense racked up 604 yards on 50 carries and found the end zone seven times.

It won't be as easy to find running lanes against a North Carolina defense that is allowing only 77 yards per game on the ground. Perhaps most astonishing is the fact they have allowed just 11 first downs via hand offs this season. Just a dominating run-stopping performance.

The Tar Heels are also 3-0 with wins over James Madison, Rutgers and Virginia. The game plan will obviously be to stop the run and force Tevin Washington to make some big throws to beat them. It's a smart strategy and it's one that will probably put the Yellow Jackets on upset alert.