WASHINGTON — Go ahead, doubt him. Take the thought of Colt Brennan succeeding in the NFL and rip it, crumple it, toss it to the side like a wad of marked-up notebook paper.

He has heard the criticism: He's too small. He's too fragile. He's a gunslinger. He's a system guy. He's a liability off the field.

He doesn't stand a chance.

"I think I learned more than anything how to battle adversity," Brennan said. "I'm the kind of guy where I have a chip on my shoulder and have tough skin. A lot of times, that's what you need in the fourth quarter to win games, and I think I have that. I have so much experience having to battle through adversity. I'm never nervous. I'm never scared."

Brennan, 24, has never been afraid to try to prove his critics wrong. For the Washington Redskins' brash rookie quarterback, training camp represents the latest episode in an effort to show he belongs among the game's elite.

His professional dreams began as a junior in high school. During Mater Dei, Calif., High's spring game, Brennan led a team of reserves against the top unit, which featured Matt Leinart. Brennan snatched the spotlight, outperforming his more decorated teammate with precision passing to lead the reserves to a stunning victory. Later that day, Brennan's father, Terry, came home and greeted his son with an eager embrace.

"Man, if you can keep doing this," Brennan remembered his father saying, "you can play in the pros someday."

Someday didn't come without struggle. In 2004, as a freshman redshirt at Colorado, Brennan was sentenced to seven days in jail and four years probation and was dismissed from the team following convictions of criminal trespass and burglary after a female student accused him of forcing himself into her dorm room and fondling her. Later that year, he transferred to Saddleback, Calif., Community College, where he played well but faced a hands-off reputation among prominent recruiters.

"There were so many negative times for me, and it was really unfair." Brennan said. "I was fighting through a lot of adversity. My main goal at that moment was to play football.

"I didn't care if I was (going to be) in the NFL. I just wanted to play somewhere, whether it was for a D-I college, a D-II college or in Canada."

Hawaii provided opportunity. June Jones, the Warriors' coach at the time, allowed Brennan to join the team as a walk-on before the 2005 season. Brennan excelled in Jones' run-and-shoot scheme, averaging 373.9 passing yards per game and setting numerous NCAA records over three seasons.

Gaudy numbers weren't enough to pacify doubts among professional scouts. After disappointing performances in the Sugar Bowl and Senior Bowl, critics drew comparisons to high-profile flameouts such as Ty Detmer and Andre Ware. He was a system quarterback, some said, flashy college fool's gold incapable of adapting to the NFL.

Weight and hip issues also were a concern. Brennan weighed 185 pounds during Senior Bowl workouts in January, approximately 40 pounds lighter than the prototypical size for the position. In April, Brennan underwent surgery to repair a torn labrum in his right hip, and some predicted he would go unselected in the draft.

"This is something I've experienced my whole life," he said of the criticism. "I've had to fight things since junior high into high school and well into college. Now, I'm at the next level, and it has never held me back from succeeding. You have to turn it into good motivation."

Coach Jim Zorn has given him the chance. The Redskins took Brennan in the sixth round, 186th overall. In Brennan, Zorn saw a bold personality with the potential to push for the No. 3 spot behind Jason Campbell and Todd Collins.

Zorn knew Brennan's hip surgery would mean an additional obstacle on a steep learning curve; because of a sedentary lifestyle during his recovery, Brennan had to drop 12 of his 224 pounds before training camp to avoid a fine. For Zorn, Brennan's confidence made the investment a gamble worth taking, and on July 14, Brennan signed a four-year, $1.8 million contract.

"Those are things that you can't coach into a guy, and he's got that a little bit about himself," Zorn said. "He's getting himself ready to play, not just run plays. It's a good attitude to have."

His attitude has given teammates pause. Brennan quickly has gained a reputation as an antithesis to the stiff, all-business field-general prototype. He wears tights on the practice field. He cracks jokes with veterans. He plays the ukulele.

"He's probably one of the most interesting rookie quarterbacks I've ever been around," Campbell said.

"He just walks around and talks about everything. ... He has these different styles that he dresses when he comes to practice. He has tights on. He has wristbands. I'm like, 'Colt, what's all this stuff you have on?' "

Said wide receiver Horace Gant: "He's cool, calm and collected. I think the Hawaii lifestyle rubbed off on him. ... He puts me in the mind of a Brett Favre-type guy. It's not the conventional, drop-back quarterback style. He gets the job done."

Brennan has embraced his new life but is cognizant of his past. At the end of a recent morning practice, fans leaned over a burgundy rail near the practice fields. They held pens, footballs, caps, stadium seats, anything to lure the subject of their attention. Moments later, Brennan walked toward their outstretched arms and flashed a faint smile before signing autographs.

"I want to go to the University of Hawaii!" a boy in the crowd said.

"I don't blame you," said Brennan, scribbling his signature.

"Is it a good school?"

"If you like the beach," Brennan said.

"In football, you set a game plan, and you get out there, and it all goes to shambles sometimes," Brennan said later. "You have to be able to bounce back. You'll throw an interception or you'll get sacked. As a quarterback, you have to be able to fight through the adversity more than anyone."