Defense follows leader

USC cornerback Terrell Thomas is not planning a speech this week.

None is required.

USC’s defense is playing with vigor and attitude that began to flourish during last season’s shutout victory at Stanford, an effort that came one week after an upset loss at Oregon State and one day after Thomas stood before his teammates and delivered an address that inspired the Trojans to a 42-0 rout.

“When he asked for the floor, I figured he would be all right,” Coach Pete Carroll said this week. “He’s worked really hard to understand how it all works and fits together. He’s a terrific disciple of the philosophy.”

Thomas, a fifth-year senior from Alta Loma, has come back from three surgeries to help lead a unit that ranks 15th nationally in total defense heading into Saturday’s Pacific 10 Conference game against Stanford at the Coliseum.

Thomas has made several big plays this season, including two that figured prominently in the Trojans’ three-point victory over Washington last week in Seattle.

The player nicknamed “T2” terminated one Huskies threat in the third quarter by stripping the ball from a punt returner and recovering the fumble. The turnover set up a field goal that put the Trojans ahead, 27-17. Thomas also came up with the ball on an onside kick after Washington pulled to within three points, 27-24, with 34 seconds left.

For the 6-foot-1, 200-pound Thomas, one of the top cornerback prospects in the 2008 NFL draft, the plays are part of a resume that he hopes to complete with another national title and postseason honors.

“I want to leave a mark at SC. I want to be an All-American,” he said. “All of us talk about it, but I truly do.”

Thomas, 22, played running back and safety at Rancho Cucamonga High but recognized he was on track to play cornerback at USC after signing with the Trojans in 2003.

“I did want to play safety, but in our defense you have to be 6-3 monsters running 4.3s at 230 pounds,” he said, referring to former safety Darnell Bing and current teammate Taylor Mays.

Thomas redshirted his first season while recovering from surgery to repair a dislocated right shoulder. He played as a reserve and on special teams in 2004, then broke into the starting lineup in 2005.

However, Thomas’ season ended in the second game against Arkansas when he suffered torn ligaments in his right knee.

“It took a lot for me to come back from that,” he said. “I grew from that into a man. I lost so much but gained so much. It kind of humbled me.”

Thomas returned last season and started every game.

His biggest moment came last November in a hotel meeting room on the night before the Stanford game.

In Thomas’ mind, the Trojans were not playing with the fire he had witnessed in players such as former linebacker Lofa Tatupu and linemen Shaun Cody and Mike Patterson.

“I just told them we needed to change things, we needed to do it now and that the defense needed to put the team on our back and start dominating,” Thomas said.

Thomas took a leading role the next day, intercepting a pass in the second quarter and returning a blocked field-goal attempt 71 yards for a touchdown in the Trojans’ first shutout against Stanford since 1989.

Thomas’ speech “helped us mainly on that night, but it also helped us get the swagger we needed to get through those final games,” senior defensive end Lawrence Jackson said. “That definitely carried over.”

The defense did not give up more than 13 points in any of its remaining Pac-10 games against Oregon, California and UCLA (the Bruins won, 13-9) as the Trojans won a record fifth consecutive conference title.

Thomas had surgery on his left shoulder before spring practice but reported to training camp healthy.

He intercepted a tipped pass at Nebraska and continued his steady play in victories over Washington State and Washington.

Thomas is confident that a defense that includes Jackson, tackle Sedrick Ellis and linebacker Keith Rivers -- all seniors -- will stay on course as the Trojans attempt to reach the Bowl Championship Series title game for the third time in four years.

Thomas is willing to speak up again but doubts that it will be necessary with such a veteran group.

“All the seniors are hungry to be the best at our positions,” Thomas said. “We all think the same thing: Why not go out on top?”

gary.klein@latimes.com