After three weeks of the 2012 NFL Regular Season, the New England Patriots sit at an unsatisfactory 1-2. The Patriots opened the season in a 'business as usual' matter, with a convincing win over the Tennessee Titans in Nashville. However, after that game, the Patriots suffered a surprise loss at home to the Arizona Cardinals and just missed out on victory in Baltimore against the Ravens.

While the Ravens game was drowned in controversy over the performance of the replacement referees and many will point to the Cardinals as being beneficiaries of a lucky performance, the Patriots' main problem lies with their own performances.

The Patriots are under .500 for the first time since 2003, when they started the season 0-1.

While the Patriots have an inexperienced group of offensive linemen protecting Tom Brady, it is veterans Logan Mankins and Dan Connolly who have struggled to this point. No, where the Patriots' real problem with youth lies on defense.

There is no doubt that Chandler Jones, Dont'a Hightower and Tavon Wilson have impressed early in their rookie seasons, but they remain rookies and rookies tend to be less consistent than veterans. It is no coincidence that the key plays of the Patriots' only victory of the season came from the three rookies.

Against the Titans Chandler Jones forced a Jake Locker fumble that led to a Dont'a Hightower touchdown, while safety Tavon Wilson intercepted a Locker pass in his own endzone to help seal the victory. In the two games since, Wilson has featured on the field much less, while Hightower's level of play has dropped significantly week-to-week. Jones hasn't played badly since the first game of the year, but his strip-sack of Locker remains the only sack he has on the season.

Considering the Patriots played against two teams with below average offensive lines since then, Jones would have been expected to make a greater impact than he has. Jones was matched up against D'Anthony Batiste against the Cardinals and Michael Oher against the Ravens. Neither Batiste or Oher will be anywhere near the best left tackle that Jones will face this year.

Even though the Patriots defense was poor for the most part last season, they did have a quality pass rush as they relied on veterans Andre Carter and Mark Anderson. Anderson and Carter combined for 20 sacks last year. Jones won't be expected to replace that production on his own, but the pressure is largely on him because none of Rob Ninkovich, Jermaine Cunningham or Trevor Scott are likely to reach double digits in sacks.

Belichick has long prioritized veteran players who understand what it means to be a professional from week-to-week. This year's culmination of talent doesn't fit that mold. This year's defense is relying on key players who are still adjusting to life in the NFL and understanding the true meaning of being a professional football player.

The difference between being a professional player and a college superstar is not simply picking up a pay check. NFL players have to be fully committed to preparation during the season from Monday through Sunday. They have to consistently be in top shape and have the sharpness of mind on the field because even the most minor of flaws will be exposed.

In college, the players could take games off and still be productive simply based on their talent levels. In the NFL, they are not significantly better than the average player at this point. The Patriots have scored at least 30 points in two of their three games this year, and scored 18 in the other against the Cardinals. Offensively Tom Brady is always going to keep them on the right track, but defensively the fans in Boston may have to live with the learning process that comes with youth in the NFL.

Cian Fahey writes for Irishcentral and the Guardian. You can follow him on twitter @Cianaf