Mark Sanchez's overall numbers in 2010 were not altogether different from the ones he registered in 2009. That is because he kept the tendency to play some real stinkers. In 2009, 17 of his 20 interceptions came in 5 games. He completed under 50% of his passes 4 times in 2010 and had a 3 interception nightmare in the 45-3 rout at New England in which he hit 51.5%.
What he did in the other games stands out, though. He had a pair of 300 yard games in 2010. He had none in 2009. He threw for 250 yards 6 times in 2010. He had just 2 such games in 2009. He had 7 multi touchdown games in 2010 against 3 in 2009. There were 4 times he threw for 3 touchdowns in 2010. He never did that in 2009.
In 2009, he was not messing up in his best games. In 2010, he was thriving and leading last minute wins against the Broncos, Lions, Browns, Texans, and Colts.
It is true that Sanchez was every bit as bad in 2010 when he was off as he was in 2009. It is important to put this in context, though. Most top quarterback prospects who start early have a lot of college experience. They have started for their college teams for 3 years, 2 at a minimum. Mark had 16 starts at USC. He is a bit behind the learning curve. He never really mastered the college game before being thrust into an NFL starting gig. He has had to learn about what you cannot do on the fly.
There was another highly regarded quarterback prospect recently who had college starting experience in the teens. His name was Aaron Rodgers. He got to sit for 3 years, learn his playbook, slowly pick things up by watching film, observing games, and practicing. When he got his chance a few years later, he started lighting the league on fire. How is this relevant? Had he been forced to start from day one, it seems like a good bet he would have battled a lot of the same inconsistency and mistakes that have plagued Sanchez.
That is why I do not buy the whole argument that Sanchez is destined to be a boom or bust guy his entire career. He came into the league really raw. He is learning on the fly. He will learn, though and become more accurate and consistent. I cannot promise you he will ever be Rodgers, but it is too early to say that a guy will be inconsistent his entire career just because he was two years into the league.
The heights are incredible. How many guys in their early 20's go into Foxborugh and outplay Tom Brady in a Playoff game? Once he gets some seasoning, the high points will probably become more regular.