Mark Sanchez has never changed. Many believe he got off to a blistering hot start, and then cooled off. Look at his numbers: they tell a vastly different story.

2009: Yards per attempt (generally accepted as the best measure of a QB): 6.7, interceptions: 20, Yards: 2,444, TDs: 12.

2010: Y/A: 6.5, interceptions: 13, yards: 3291, TDs: 17.

2011: Y/A: 6.4, interceptions: 18, yards 3474, TDs: 26.

2012: Y/A: 6.4, interceptions: 18, yards, 2883, TD: 13.

For example, look closely at 2009 and last year. They are incredibly similar. Sanchez didn’t deteriorate. The New York Jets did. In 2009, the Jets had the best defense in the league and a top-five running game. In 2010, they used the same formula and went deep into the playoffs, two years in a row by that time. By 2012, the Jets team lost its potent run game. While they had a good defense, it certainly was not dominant.

Sanchez is the same player he always was; don’t buy the narrative that he has changed. But that is exactly the issue. Young quarterbacks have to get better. Sanchez didn’t. He was a stellar rookie quarterback in 2009, but great rookie quarterbacks are still below-average NFL quarterbacks. Sanchez’s tale is not one of a player falling apart, but of one stagnating.

The mistake the Jets have made was in treating Sanchez like he would improve. Two years ago they gave him a new contract worth over $8 million a year. That kind of money is for solid quarterbacks, not the Trent Dilfer-types who use great defenses to make them appear better than they are. As of now, Sanchez is making more than Robert Griffin III, Andrew Luck, Russell Wilson, Cam Newton and Colin Kaepernick. Combined. Those young quarterbacks will have to show continued improvement to get big paychecks, but somehow Sanchez didn’t.

Sanchez is set to have surgery that will end his season, putting him at a crossroads for his career. The Jets will surely let him go and tag along with Geno Smith. The young West Virginia-product has already shown great promise and has the talent to be a star. Sanchez’ new home will probably involve a lot of holding clipboards and watching another quarterback play.

Truth be told, Sanchez is overqualified for that. He has the skills to be a starting quarterback, just not an above-average one. However, in this day in age, teams need an above-average quarterback to win. Taking a chance on a young player who is unknown is worth more than having a steadily mediocre passing game.

Sanchez’ career fell apart not because his game did, but because he never got better. Sanchez moved at a steady pace, but in an NFL with young guns breathing down your neck, that simply isn’t an option.

Jay Cullen is a New York Giants and NFL writer for www.RantSports.com. Follow him on Twitter or add him on Google.