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No fan of the New England Patriots wants to know how good Matt Cassel really is, but the backup QB is ready to go if Tom Brady can’t.

SCOTTSDALE, Ariz. — Matt Cassel didn't see the photo. Not at first. It wasn't his business to know that Tom Brady had gone to New York to visit his girlfriend.

Wearing a medical boot to stabilize a sore ankle. After the Patriots had beaten the Chargers in the AFC championship game, leaving the Patriots with one last game to win for its perfect season.

Cassel was oblivious to the building furor after the photo was seen. Until his phone started to ring and his server was flooded with e-mails from the Matt Cassel Fan Club, better known as friends and family.

"I got maybe 100 e-mails," said Cassel. "A lot of them said the same thing."

Which was?

"No better time for a first start than the Super Bowl."

That's not happening. Even though Cassel took more snaps in practice last week than he's had in months. While Brady teased or worried football fans by disappearing from practice before the team left for Arizona, Cassel knew better.

"I know Tom's history. I knew it wasn't going to be an issue. But I can't be complacent. I've got to work harder," he said.

Cassel is 25 and hasn't started a football game at quarterback since he was in high school. He was the backup to Heisman winners Carson Palmer and Matt Leinart at the University of Southern California. Cassel thought the starter's job was his before his last season, but it went to Leinart, instead.

"I thought of transferring, but I went to USC for a reason. It's a great school. I wanted to get my education there, it was close to home and I really don't like to quit what I started."

So he stayed. Not one NFL scout spoke to him after his last season. He wasn't invited to the NFL Scouting Combine where hundreds of hopefuls show their stuff. Instead, he went to the Pro Day at USC. "What did I have to lose?"

Afterward, 10 NFL scouts handed Cassel their business cards. They'd be in touch. On draft day in 2005, Bill Belichick took him with the team's last pick.

This season, Cassel threw seven times, completing four. Brady had 578 attempts, completing 398. Brady, by Cassel's estimate, took between 95 to 100 percent of the snaps during any practice week.

"I had to rely on mental snaps," said Cassel. Game days were roller coasters, intense, emotional. Playing mentally, but not physically.

When Brady called a play call in the huddle, he would do the same on the sideline. Cassel had to keep his head in the game. Just in case.

Scott Zolak, the No 2. quarterback behind Drew Bledsoe 15 years ago, once said he was exhausted when he walked off the field and he didn't get in the game. Cassel agreed. He heads for the showers, even though he never broke a sweat. When the hot spray hits, he can relax.

Wednesday, as Cassel spoke, dozens of media members jostled each other trying to get closer to Brady, who sat nearby behind a table on a hotel riser. The other lanky, good-looking quarterback might have been invisible. Not that Cassel is complaining.

"I wouldn't trade this experience for anything. Being around Tom Brady for two years has meant so much to my development as a quarterback. Tom has been my biggest supporter. He's always building me up, telling me there's a reason (I'm) here."

No Patriots fan wants to learn that reason Sunday. Put the end to this historic season in the hands of a quarterback who threw 32 passes in four years of college and 39 in three years in the NFL? He has passed for two touchdowns, and this year, against Washington, scrambled 15 yards for his first rush into the end zone.

"I got to spike the football. It was pretty cool. If Tom has to come out, my job is to not make the bad play," said Cassel.

"My job isn't to make the big play."

Last year, 43-year-old Vinny Testaverde, a former Heisman winner, was the Patriots' insurance policy. Two years ago, it was Doug Flutie, another veteran...