Click-clack, the players march down the sidewalk, through a corridor and onto a paved street. Students watch and shout encouragement as this sonorous procession trudges to the opening summer practice of USC's 2005 season. At first, few notice the highly touted freshman quarterback, Mark Sanchez, as he passes by the crowd.

Sanchez chose USC not just because of the program's star power, but also because it kept him close to his family in Southern California. He didn't care that it meant he'd likely sit on the bench for two seasons, maybe three. He didn't care that, for awhile, he'd be as faceless to fans of the program as the Trojans water boy.

Or so he thought.

As he click-clacks through the gate and onto the practice field this summer day, Sanchez sees them before they see him: men in Mexican wrestling masks and serapes, flanked by other fans carrying signs of support. For him. When the crowd finally recognizes him, a cry goes out: "¡VIVA SANCHEZ!"

It is at this moment that Sanchez realizes he is playing for not just himself, his family and his team. Whether he likes it or not, he's playing for people whose names sound like his; for those from south of the border who work thankless jobs for little pay; for those who are reminded daily that they live in a country that does not know what to do with them. These are the fans who once cheered for Valenzuela and Plunkett and now cheer for Garciaparra and De La Hoya. They are his fans too. On this day, Sanchez has arrived in Los Angeles.

Jeff Garcia. J.P. Losman. Tony Romo. All quarterbacks of Mexican descent, yet Mexican-Americans haven't embraced them the way they cling to USC's QB. If there's pressure that comes with that, Sanchez—whose long, curly black hair makes him look like a brawnier Vince Chase from Entourage—is well-equipped to bear it. The Trojans recruit transcendent athletes who arrive as great prospects and leave as television pitchmen. They are preter-naturally poised, their showmanship skills honed sharper every season. Sanchez has embraced this role, which has allowed him to re-embrace his roots.

The lure of work—lots of it, even for low wages—compelled Mark's great-grandfather Nicholas Sanchez to move his family from south Texas to California in 1911. Born in Zacatecas, in central Mexico, Nicholas, like his wife, Isabel, was a day laborer. They were fruit pickers in California's Central Valley, a bountiful stretch north of Los Angeles. The work was arduous but sustained a family with six children, including one named Jorge, born on George Washington's birthday.

At the same time Nicholas moved his family west, Pedro Moreno from Jalisco, on Mexico's central Pacific coast, transplanted his brood to Bisbee, Ariz. Pedro was a large man by Mexican standards, 6'2" with broad shoulders and a booming voice. He became a successful real estate investor known for wearing a hat, coat and tie even during the cruelest heat. His fortune allowed Pedro, who spoke little English, to move his wife, Rosa, and their 16 kids to Los Angeles in 1925. One evening, their daughter Juanita brought Jorge Sanchez home for dinner.

They married soon after and started a family, each generation more rooted in America and less connected to its past. Jorge, a World War II vet, and Juanita raised four kids in LA's projects before moving to a house in South Central, a mostly black community. The Sanchezes were not wealthy, but they lived comfortably on Jorge's salary as an aeronautics technician. Their youngest child, Nick, was the most mischievous, and he would wander USC's nearby campus with his friends. He noticed that the students were mostly white and never thought anyone who looked like him would be able to attend such a school.

Born in Long Beach, Calif., Mark Sanchez never thought much about being Mexican, except when he ate enchiladas at family barbecues and dined on tamales at Christmas. His father, Nick, had grown up in a black neighborhood. His mother, Olga, had been one of the few Mexican-Americans in a mostly Jewish part of East LA. Nick and Olga divorced when Mark was 4, and Nick raised his sons in a white neighborhood in Orange County. Olga, a day-care worker in Whittier, made three-hour bus trips to stay involved in her sons' lives. The parents were determined to live in the present for their kids, leaving little time to focus on the family's past.

Nick, a captain for the Orange County Fire Authority, and his second wife, Maddy, were strict with his sons: Nick Jr., Brandon and Mark. The boys could never skip commitments, even Little League practices. When meeting a new person, the Sanchez kids had to be the first to introduce themselves. Nick even forced them to make speeches at PTA meetings. He wanted to raise communicators. Even now, he ends every phone call with his sons by saying, "Be a leader."

"The lessons set them apart," Nick says. "They gave them the ability to separate from folks."

When Nick Jr. left home to play QB at Yale in 1991, Nick Sr. insisted that his eldest son write often to Mark and Brandon (who went on to play offensive line at DePauw). "At one point in time, they're going to be your best friends," he told Nick Jr., now a lawyer. It's a message—a mentality—that resonates with Mark. "When things are going right, you're going to have a lot of friends," Sanchez says. "Everyone is going to be associated with you, and you should appreciate that and be flattered. But when everything is said and done, it's going to be my brothers, my parents and a handful of close friends."

When Mark was 13, he accompanied his father on a trip to Nick's old South Central neighborhood. The boy was aghast at what he saw. Manual Arts High School, which Nick attended, was fenced in to keep troublemakers out. The houses, which had never been posh, were in disrepair. This was Nick's point: to show his son where he had come from. He ended the tour with a trip to USC, just like the old days. Nick snuck Mark into the football locker room, where they ran into the equipment manager. Boldly, Nick asked if his son could have a couple of wristbands. The manager, a heavyset Mexican-American, took pity on the Mexican and his son and handed some over.

Soon enough, Sanchez wouldn't need any favors. As a junior at Mission Viejo High, playing for QB guru Bob Johnson (father of former NFL and USC QB Rob Johnson), Sanchez threw 29 TDs and just seven picks. Because of his smarts and arm, every school in the country was after him. There were dalliances with Texas, Notre Dame, Nebraska and Ohio State. Sanchez remembers Jim Tressel sitting behind his desk in the Buckeyes' football office, delivering his pitch: "Mark, you know the two most important people in the state of Ohio are the governor and the quarterback for Ohio State."

Tressel then paused before adding, "And the quarterback for Ohio State is No. 1."

Despite such hard sells, Sanchez, the top-ranked drop-back QB prospect in the country, announced for USC the summer before his senior year. And it wasn't just the program's glamour—or that pipeline to the NFL—that sold him. He was comfortable at USC, what with so much family history nearby.

Once he was on campus, his first two seasons were very much as expected: unremarkable. Until last October, anyway, when, as a redshirt sophomore, he replaced the injured John David Booty for three games. Sanchez gave a nod to his heritage, a gesture to all those fans in wrestling masks and serapes who had cheered when he click-clacked across the concrete that first time. He wore a tricolor mouthpiece that team dentist Dr. Ramon Roges, who is Cuban, made to look like the Mexican flag. For Mexican-Americans, it was a symbol of solidarity—Sanchez publicly accepting his roots. For detractors, the gesture symbolized radicalism, a small-scale equivalent of John Carlos and Tommie Smith raising gloved fists at the 1968 Olympics. And for the first time, USC's football office received hate mail, phone calls and e-mails aimed at Sanchez. "Racism could've been part of it," says Sanchez. "That's just someone's personal opinion, just like it was my prerogative to wear the mouthpiece. That's the country we live in. People can say whatever they like. Their views on it might not be why I wore it, but they have their right to say whatever they want. It was just an innocent gesture."

Sanchez is not political—he won't take a public stance on immigration or endorse a presidential candidate. And he is far from perfect, having been involved in more than one alcohol-related incident at USC (one of which drew a suspension). So as a public face for Mexican-Americans, he is a curious choice. But his status speaks to his high-profile position and his on-field persona. "His maturity was above and beyond any high school kid I had ever met," says Cal offensive lineman Kevin Bemoll, a former Mission Viejo teammate.

So now Sanchez talks to high school kids from predominantly Mexican East LA. And for the first time in years he is taking Spanish classes, so that he doesn't disappoint Mexican fans who approach him speaking their native tongue, hoping he really is like them. "It's just an opportunity to give back to them as much as possible, in appreciation for their support," says Sanchez, sitting in the mess of an apartment he shares with fullback Stanley Havili.

USC's campus still does not reflect LA's demographics—only 14% of the student body is Hispanic in a city where 47% of the population is Latino. And while the Trojans are a diverse mix of blacks, whites and Pacific Islanders, there is not a strong Hispanic representation. Not that Sanchez notices. Unlike LA's neighborhoods, USC's locker room isn't divided along racial lines.

And like almost every Trojan, Sanchez is thinking about playing on Sundays. But to do that, he has to protect his job on Saturdays. Last season, he threw two interceptions in a win against Arizona and beat up on overmatched Notre Dame. But he then made several mistakes, including a fourth-quarter pick in a loss at Oregon that ultimately cost USC a national-title shot. Still, those three starts—and the way he publicly took the blame for the Oregon loss—helped Trojans coaches decide he should start this season over Arkansas transfer Mitch Mustain. "Mark has energy, he's outgoing," says head coach Pete Carroll. "And he's really connected to SC football. He's really grown up to be an SC quarterback."

This spring, Sanchez ran the Trojans offense with enthusiasm, sprinting to congratulate receivers after completions ("Good catch, Vidal! Good catch!") and encourage them after drops ("C'mon, Brod! C'mon!"). Following his own misfires, he chased down coaches for advice: "Was it zone? Was it zone?" It's hard to say whether his repetition stems from his exuberance or a need to make sure he's been heard. And it might not matter.

"I think he's going to have a positive effect on our football team," says offensive coordinator Steve Sarkisian. 'I'm anxious to see how he does."

He's not the only one.

For a piece by the writer on how this story came together, please go here.

For a video look at some great USC quarterbacks of the past, please go here.

For a photo gallery of some pictures taken at Mark Sanchez's recent family BBQ (and other pics), please go here.