For his entire football career, the short, under-the-radar Julian Edelman has been seen as the underdog, but on the NFL's biggest stage, he could take the opportunity to prove otherwise.

PHOENIX -- Even by the carnival-barking standards of Media Day, Julian Edelman attracted an odd and offbeat strain of questioners, such as the guy who needed to know his go-to gas station snack (Corn Nuts, as it turned out), the woman who asked him to explain "what is a rub route?" and the NFL Network’s Michael Irvin, who ended their interview with the touching endearment, "Way to keep playin’, baby. You are my dog, man."

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The truth, although neither would admit it, is that Edelman is Bill Belichick’s dog: a hyper-competitive, workaholic, video-devouring gym rat who "will catch 200 balls before some guys walk in the building," says Patriots receivers coach Chad O’Shea. During his days as a Kent State quarterback, Edelman was known to run down the field and physically accost a receiver in practice, if he felt that player hadn’t given the proper effort.

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Now in his sixth NFL season, the shape-shifting Edelman -- he also returns punts, has lined up at defensive back and threw a 51-yard touchdown pass to Danny Amendola in New England’s divisional round win over the Ravens -- has succeeded Wes Welker as Tom Brady’s go-to guy in the slot. Edelman, whom Brady occasionally refers to as "Minitron," has caught 197 passes in the last two seasons, only slightly higher than the number of questions he fielded on Tuesday about his Dinty Moore beard. (“Have you seen what’s goin’ on in the northeast? Gotta keep this face warm.”) Consistently gracious though he was, he seemed underwhelmed by the nickname he and Brady and several other well-coiffed Patriots had earned: The Legion of Groom.

"Well-groomed?" he asked, mildly incredulous. "I have a beard on my face that looks like a squirrel."

Who had the team’s best beard? "[Rob] Ninkovich," he replied, without hesitation. "He’s got a man’s beard. I’ve got a little boy beard."

Speaking of children, a youngster at Media Day asked Edelman to give advice "to somebody like myself wants to be a great football player." He told the kid to "be well-rounded, take care of your schoolwork, listen to the people that are guiding you." He urged another boy to "find your talent, and chase your dream." Funny he says that...

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“He dominated until he was around twelve,” recalls Edelman's father Frank, who owns an auto body shop in Mountain View, Calif. “But when he got to high school, that’s when he had a no-growth spurt.”

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Frank coached his son in Pop Warner; their team won a under-12 peewee national championship. After that it was downhill for a while for Julian. “He didn’t hit puberty 'til he was, like, 17,” says Frank. “When he got to high school he was 5-foot-2 and 100 pounds. All those guys he used to dominate started dominating him.”

Finally, between his junior and senior years, Julian sprouted a half-foot and put on 50 pounds. As a senior, he quarterbacked the Woodside High Wildcats to a 13-0 record, but remained a secret to Division I coaches. Thus he found himself at San Mateo College, where his first pass, recalls Bret Pollack, now the head coach at that junior college, “was a touchdown … to the other team.”

Once he got the offense figured out, Edelman amazed, earning the starting job after two games. “When you have an athlete like that,” says Pollack, “you put the ball in his hands every play. Julian just had an innate sense of seeing the game three or four moves ahead of everyone else on the field.”

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He got some minor feelers from Pac-10 schools. But coaches wanted him to play another season at San Mateo. “I wanted to go to Cal real bad,” Julian told SI earlier this season. “But everyone wanted me to stay there in [junior college], or they wanted me to change positions.” He had Doug Flutie’s No. 7 Chargers jersey in his bedroom. “And I had this foolish pride, I wanted to be a quarterback.”

Sounds like a plan, the coaches at Kent State told him. And so, after just a semester at San Mateo, he signed on with the Golden Flashes, a middling Middle American Conference program that already had a hotshot juco transfer at quarterback. Michael Machen, from Coffeyville Community College, in Kansas, was working on his “quick kicks” one day in practice when the new guy from California approached him.

“Jules walked up to him and says, ‘Better keep practicing those, ‘cause I’m taking your job,’” recalls Frank. And so it came to pass. A three-year starter for coach Doug Martin, Edelman finished with a flourish. As a senior, he led the nation in rushing yards by a quarterback (1,370), going over the century mark in a game eight times. He passed for another 1,820 yards, and finished his college career with 52 touchdowns.

On Thanksgiving Day in 2008, Frank took a call from the BC Lions of the Canadian Football League. They wanted Julian to play quarterback for them.

“Absolutely not,” he answered. “I’m going to the NFL.”

That was going to be tricky, considering that he was not invited to the NFL scouting combine.

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Instead, he focused on Kent State’s pro day. To prepare, he rose at 4 a.m. six mornings a week, and drove his distressed pickup truck the hour or so to a gym in Cleveland where a group of other Midwestern studs, guys from Michigan and Ohio State, were prepping for the Combine. By this time, Edelman knew that his NFL future, if it existed, was not at quarterback. He immersed himself in making the transition to receiver, glomming onto ex-Akron quarterback Charlie Frye, then with the Raiders.

“If he wants something, Jules can be relentless,” says Frank, recounting that his son would constantly pester Frye, asking if he wanted to get together and throw the ball. As many times per week as Frye agreed to do it, those two met at Akron’s workout facility, the ex-Zip throwing passes to the former Golden Flash.

Edelman, not surprisingly, crushed the Kent State pro day. His 4.51-second 40-yard dash was faster than any quarterback at that year’s Combine, and would’ve placed him 15th among receivers. His short shuttle and long shuttle times -- 3.91 seconds and 10.74 seconds – were faster than any recorded at that year’s combine. So off the charts was his short shuttle that scouts, suspecting they’d bungled the hand timing, asked him to do it again. He ran it faster.

He was short, under the radar, played multiple positions, smoldered with intensity and rose each morning determined to prove to the world that he belonged in the NFL, that the scouts were wrong about him. He was, in brief, the perfect late-round Patriots draft choice. After working him out privately, they took him in the seventh round.

The player whose focus and passion were too much for some of his college teammates had found his tribe, his people. He and Belichick belong together. “Love him to death,” says Edelman of his coach, “But I know the day I can’t do my job, or there’s someone else out there, I’ll be replaced.”

How he does his job Sunday will go a long way towards determining the outcome. It will be his sternest test of the season, as Irvin took pleasure in reminding him, as the cameras rolled:

“What about Kam Chancellor now, [with] you roamin’ the middle of the field … He’s a big hitter. How concerned are you?”

Edelman replied with respect, but also without fear. In a Super Bowl crowded with underdogs, few are as underdogged as this son of an auto mechanic, who has spent his entire playing career upending expectations. Someone needed to be asking the Seahawks how concerned they were about him.