If a quarterback sends the wrong message to his receivers, it could cost him the football.

If a quarterback sends the wrong message at this week's NFL scouting combine in Indianapolis, it could cost him $10 million or more.

That's why USC's Mark Sanchez and his handlers are especially careful these days about the signals he's sending. With the top of the draft still very murky, and Sanchez a legitimate candidate to go No. 1, everything counts — every impression he leaves, every word he utters, and every minute he spends preparing to wow talent evaluators.

His message: Forget Tinseltown, I'm all about football.

"There's a lot that comes with being an SC quarterback," said Sanchez, who was initially reluctant to be interviewed because, he said, he wants to stay under the radar before the combine. "There's Hollywood, there's downtown L.A., there's fun places to go for a young college kid. But at the same time, what's most important to me is being a good football player. I think I learned a lot of that from a guy like Carson Palmer and a lot from J.D. (Booty) as well. They've both been hard workers."

Conspicuously absent in that is a mention of Matt Leinart, the Heisman trophy-winning USC quarterback now holding a clipboard behind Kurt Warner with the Arizona Cardinals. Fair or not, the perception Leinart was Mr. Hollywood not only hurt his draft status — the onetime potential No. 1 pick slipped to 10th — but has likewise dogged him in the pros.

"What teams want from a franchise quarterback is, after God and family, football better be next," said Mike Mayock, scouting expert for the NFL Network. "You'd better have a passion for the game of football. ... I want (Baltimore's Joe) Flacco and (Atlanta's Matt) Ryan, two kids that the day after they had a playoff loss this year were both back in the tape room breaking down tape trying to figure out why.

"I don't want some guy out running the streets chasing starlets. I'm not saying that it's a USC quarterback thing. I'm saying that Matt Leinart may have had a reputation which worked against him and may have borne out a little bit."

Sanchez is especially careful not to criticize Leinart, saying he's "a great football player, and that's going to surface again real soon." But it's clear that Sanchez is determined to distance himself from any suggestion that he's a man about town, or focused on anything but football.

And for good reason. The No. 1 pick in the 2008 draft, Miami Dolphins tackle Jake Long, received $30 million guaranteed. The 10th pick, New England Patriots linebacker Jerod Mayo, got $13.8 million.

But Leinart also had something that Sanchez doesn't. Namely, a long and distinguished college career. Whereas Leinart won the Heisman and a national championship, Sanchez has started just 16 games, orchestrating just one fourth-quarter comeback. His most impressive performance was his last. In a 38-24 victory over Penn State, he set a Rose Bowl record by completing 80 percent of his passes (28 of 35) for 413 yards and four touchdowns.

How much difference can one outstanding bowl performance make? It did wonders for LSU's JaMarcus Russell, who rocketed ahead of Notre Dame's Brady Quinn with an eye-popping performance in the Sugar Bowl — in a victory over the Fighting Irish.

That was by far the most dazzling jewel on the resume of Russell, who was taken first overall by the Oakland Raiders a few months later.

This year, the Detroit Lions have the No. 1 pick and an inordinate amount of pressure to make the right move, considering they're coming off the NFL's first 0-16 season. They will take a hard look at the two top quarterbacks in this class, Sanchez and Georgia's Matt Stafford, but the Lions have plenty of holes to fill.

Quarterback is also high on the wish lists of three other teams that pick in the top 10: Kansas City at three, Jacksonville at eight, and San Francisco at 10.

The top of the quarterback ladder would have been a lot more crowded if not for the decisions of three elite prospects to stay in school: 2008 Heisman winner Sam Bradford of Oklahoma, 2007 Heisman winner Tim Tebow of Florida, and Texas standout Colt McCoy.

Some scouts believe that while Stafford might have a stronger arm and more experience, the elusive Sanchez — who has shown a knack for making plays out of the pocket — has more upside potential.

"I think I have a deceptively strong arm," Sanchez said. "I made some throws this year that surprised some people, off my back foot over the middle in tight windows. ... My arm's been closer to Carson's than anybody at `SC."

The way Sanchez sees it, his work ethic and passion for the game set him apart.

"All my focus is on, `How are we going to win on Sunday? How am I going to make these guys around me the best?' " he said. "I'm excited about the opportunity to have all day to devote to something like that. That really drives me."

Mayock said it was easier to evaluate the two quarterbacks selected in the first round last year — Ryan at No. 3, and Flacco at 18 — because both were fifth-year seniors with more robust bodies of work.

"I felt a lot more comfortable endorsing those two kids as franchise quarterbacks than I do Stafford and Sanchez," Mayock said. "Not necessarily because they're not talented kids — because they are."

For the past few weeks, Sanchez has followed a strict daily training regimen in Orange County, Calif., with his personal quarterback coach, Bob Johnson, fine-tuning for his performance at the combine and subsequent pro day on campus.

According to his brother Nick, who is also serving as his agent, Sanchez has yet to decide whether he will throw for scouts at the combine. Mark will make his decision on that in the next couple of days. In recent years, it has become increasingly common for top quarterback prospects to wait until their pro day to throw.

Even if he decides not to throw at the combine, Sanchez will have a lot on his plate. He will take all the psychological and intelligence tests, undergo hours of medical testing and evaluations, and interviews with team executives that will stretch late into the evening. Typically, quarterback evaluations are performed over three days.

There's a good chance he'll be asked about his last news conference at USC, an awkward affair in which Coach Pete Carroll made it clear both in his words and body language that he thought Sanchez made the wrong choice in leaving early.

"That was just Coach's competitive juices coming to the forefront," Sanchez said. "I didn't take that offensively at all. That to me was a sign of respect. It was flattered. The best college coach around, one of the best coaches ever, wanted me back on his team. So that says a lot."

No one disputes there was a chill in the room.

Now, the best Sanchez can hope for is a different kind of icy reception. From Detroit.

Asked if he would relish playing for the Lions, he didn't hesitate.

"Oh, I'm there," he said. "I'll get a nice big jacket and be ready to play ball."