When I last looked, the New England Patriots were favored by 2.5 points heading into the Super Bowl this weekend against the New York Giants. For most of the Patriots' roster, that is an unusual feeling.

Despite Tom Brady's career as a superstar in the NFL, Brady still holds onto the fact that he was the 199th overall draft pick in 2000 as motivation for his career. Brady's road to NFL stardom is a celebrated underdog story but there are plenty of other parts of the Patriots' roster who are going unnoticed.

Brady's main backfield mate, BenJarvus Green-Ellis, did one better as he went undrafted completely in 2008 before winning the starting job for the team as a rookie. The former Ole Miss product didn't initially make the roster being waived prior to the season. The Patriots retained him on their practice squad before he made his first start in place of Laurence Maroney on Monday Night Football against the Broncos.

As one undrafted player carries the running game, another leads the team in receiving.

Wes Welker may now be renowned as one of the best receivers in the NFL, but after his college career at Texas Tech, the best he could do was land an opportunity to play in San Diego, where he lasted one game before being released. He went unclaimed on waivers before accepting a role with the Miami Dolphins as a special teams player. He eventually found his way to the Patriots via trade and the rest is history.

While Welker is the team's leading wide receiver, Tom Brady's primary target didn't exactly sail into the NFL.

There is a lot of talk about Rob Gronkowski's ankle this week ahead of Super Bowl XLVI in Indianapolis, but it was Gronkowski's back that ultimately caused the elite talent at tight end to fall into the second round of the 2010 NFL draft. While the second round is still a top tier of the draft, Gronkowski had question marks over whether he could ever actually play the game at this level considering he missed his entire final college season to have back surgery.

Had that not happened, he likely would never have made it to the Patriots' roster.

While most of the Patriots' offensive line was heavily invested in by Bill Belichick, two of the team's most pivotal starters heading into the Super Bowl weren't drafted by Belichick. After Dan Koppen went out early in the season, the Patriots turned to former starter at guard Dan Connolly.

Not only was Connolly undrafted, he had only previously started one season entering this year, at a different position. Connolly stepped into the vital role of playing center for the Patriots without any extensive experience playing the position. Protecting Tom Brady through the middle is massive for the Patriots gameplan.

In Connolly's previous guard spot, 34-year-old Brian Waters took over as a starter this year after being released by the Chiefs for cap concerns. Waters also was never drafted before finding a spot on the Dallas Cowboys practice squad. Eventually he found his way to the Kansas City Chiefs, where he spent a decade, and ultimately landed with the Patriots in what is likely to be his final season.

The theme of aging veterans and undrafted free agents continues when you switch to the other side of the ball.

Mark Anderson may not have been an undrafted free agent, but very few people were celebrating his selection in the fifth round in 2006. Anderson had a fine rookie season, notching 12 sacks as a Chicago Bear, but since then his career had, for the most part, made him irrelevant.

Anderson was a cheap pickup for the Patriots ahead of this season, but proved to be a valuable commodity. He wasn't a starter for the team until Andre Carter went out, but he still managed 11 sacks in the regular season.

Anderson will be lining up across from a player who suffered a similar fate to Brian Waters.

Shaun Ellis, at 34 years of age, wasn't a high priority for the New York Jets after last season. The Patriots still saw a lot to like in the aging veteran by paying him over four million dollars to play this season.

Ellis has had an underwhelming season, if he was to light up the big stage in Indianapolis, it would mark a major turnaround for him from the regular season and serve notice to his previous franchise in New York.

While Vince Wilfork leads the team's defensive line from the inside, his partner in the rotation returns us to another undrafted free agent.

Kyle Love may not be starting in the 3-4 defense, but he will see substantial time as a rotational guy and should the team flex between formations. Love went undrafted in 2010 but has, for the most part, been a solid player for the team.

The Patriots rotational front seven only really features one marquee player in Vince Wilfork. Considering the group previously contained Wilfork, Ty Warren and Richard Seymour, it is almost inconceivable that the Patriots are even in this Super Bowl.

For the most part, the Patriots linebacking corp is made up of recognizable names, but Rob Ninkovich continues to keep the underdog theme running through the roster as a whole. Ninkovich has bounced around between teams during his seven season career, but the Patriots made good use of his versatility this year.

Antwaun Molden may have been a third round pick of the Houston Texans in 2008, but he has only started two games in his four year career. Molden, along with Kyle Arrington who leads the team in turnovers, has become a key fixture for the Patriots' secondary after Devin McCourty's struggles this year.

While Molden was a third round pick, Arrington was overlooked—quite literally—coming out of Hofstra as being too small to play the position. Instead, Bill Belichick has made use of his instincts and intelligence to get the best out of the undrafted free agent.

Entering training camp this year, the Patriots had three starting caliber safeties on their roster. While Brandon Meriweather was a freelancer and massively overrated nationally, he was still a capable starter for the team. James Sanders was inexplicably let go while Pat Chung is the only remaining starter from the trio.

Chung has seen Devin McCourty join him on the back end, while Sterling Moore has made a name for himself in the playoffs.

Moore is a rookie who has only played in eight career games after bouncing around from the Raiders' practice squad, to the Patriots' practice squad, to the Patriots' active roster, back to the practice squad and now the active roster once again.

The New England Patriots may be the favorites this weekend, but this group of players will be using the motivation of being rejected over and over again to propel themselves to the top of the NFL world.

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