LOS ANGELES — Southern California quarterback Mark Sanchez will skip his senior season to enter the NFL draft.

Sanchez and Georgia's Matthew Stafford, another junior coming out early, are considered the top two quarterback prospects in the draft. Heisman Trophy winner Sam Bradford of Oklahoma decided to return to school.

Sanchez is coming off a spectacular Rose Bowl against Penn State. The fourth-year junior went 28-for-35, setting a Rose Bowl record by completing 80 percent of his passes. He threw for 413 yards and four touchdowns, and also ran for a score in the Trojans' 38-24 victory.

"In the end, after sleepless nights and lots of prayers, I've decided I'll forgo my fifth year and declare for the NFL draft," Sanchez said Thursday at a campus news conference. "It is with a heavy heart I am going to leave this university."

Thursday was the deadline for underclassmen to declare for the NFL draft.

Trojans coach Pete Carroll tried to talk Sanchez into coming back for another year, noting that he started only 16 college games and NFL teams often prefer quarterbacks with more experience.

"Mark is going against the grain and he knows that," Carroll said. "And he's OK about that."

Sanchez started just one full season at USC, leading the Trojans to a 12-1 record and No. 3 national ranking. He started three games the previous year when John David Booty was hurt, going 2-1 in those contests.

Sanchez is the fourth in a line of outstanding quarterbacks to play under Carroll at USC, joining Heisman Trophy winners Carson Palmer and Matt Leinart along with Booty. All three are playing in the NFL.

Palmer was the first overall pick in the 2002 draft and Leinart was selected 10th in 2005. The 6-foot-3, 225-pound Sanchez is the only one of the four to leave school early for the pros.

Dressed in a snappy suit, Sanchez said he plans to complete his undergraduate degree at USC this spring.

"I'm not quite leaving early," he said. "I'm just forgoing my fifth year."

A high school star in nearby Mission Viejo, Sanchez finished this season with 3,207 yards passing, 34 touchdowns and 10 interceptions. He passed for 695 yards and seven touchdowns with five interceptions as a sophomore in 2007, and 63 yards and no touchdowns with one interception as a freshman in 2006. He redshirted in 2005.

After the Rose Bowl win over Penn State, many in the crowd of 93,293 chanted "One more year!" to Sanchez.