The low point? You want to know the low point for Mark Sanchez during his career with the New York Jets? You want an understanding of and appreciation for how far he's come, how different everything is for him, now that he has assumed the Eagles' starting quarterback job because of Nick Foles' cracked clavicle?

Seriously, you want to know how bad it was?

Good luck with that. Good luck plumbing those depths. It's impossible to pinpoint just one moment. Think about this: Over the final 51/2 weeks of the 2012 season, the last one in which Sanchez took a regular-season snap for the Jets, the following happened:

He was involved in what might be the greatest gaffe in football history - the "butt-fumble" on Thanksgiving night against the New England Patriots. The following week, he threw three interceptions and was sacked three times and was benched at midgame by coach Rex Ryan. Two weeks after that, he threw four more interceptions and lost a fumble on Monday Night Football, in an infamous loss to the Tennessee Titans that eliminated the Jets from playoff contention.

Ryan benched him again, but then Sanchez's replacement - Greg McElroy, who isn't even in the NFL anymore - suffered a concussion. So Sanchez started one more game: Dec. 30, 2012, against the Buffalo Bills. He threw an interception that was returned for a touchdown. The Jets couldn't score one themselves. They lost.

That ugly history is worth mentioning not because Sanchez is likely to repeat it with the Eagles, but because he isn't. He's starting for a 6-2 team in a quarterback-friendly system, for a quarterback-friendly coach in Chip Kelly, for a fan base that won't much care what Sanchez does with his free time as long as he continues to play at least as well as he did in the Eagles' 31-21 victory Sunday over the Texans.

This situation isn't comparable to the mess that the Jets had become (and still are) and to the peculiar public fascination that accompanies being the latest Next Joe Namath. If you thought we psychoanalyzed Donovan McNabb over his decade here, you're only beginning to have an idea of how people pored over Sanchez's every throw, every word, every move off the field. (And remember: McNabb never attended the Tony Awards, and he never posed for the cover of GQ.)

Sanchez basically spent five years on a black couch in the nation's biggest media market. Everyone, from fans to former teammates, turned into an amateur Freud or Jung, trying to account for Sanchez's regression from a quarterback who helped the Jets reach back-to-back AFC championship games to one who committed an NFL-high 52 turnovers over the 2011 and 2012 seasons and lost 12 of the final 18 games he started.

One popular theory: Sanchez had been coddled his whole life. He'd grown up in Orange County, Calif., and had attended two football factories: Mission Viejo High School and Southern Cal. The Jets had traded up to draft him with the No. 5 overall pick in 2009 and immediately had placed him in a protective bubble, limiting his media access, building their team around their terrific defense and running game, doing all they could to minimize his effect on a game's outcome, asking him not to foul up anything for 60 minutes, then smile that winning quarterback smile for the cameras afterward. Oh, and his father, Nick, had attended virtually all of Mark's games - in high school, in college, in the NFL - and was a ubiquitous presence around the Jets. So Sanchez probably had daddy issues, too.

"Instead of feeling his oats as a man, he's always tried to keep everything structured correctly because Daddy's around," former Jets defensive tackle Kris Jenkins told me in 2012. "He doesn't want to be disrespectful. He doesn't want to do things that might come off as being insulting, and those are the things that might hinder him if Dad is around too much. At some point and time, Sanchez has to be a man."

Questioning a quarterback's manhood can make for a juicy quote in a tabloid-style story, and sure, Sanchez, who became the Jets' starter when he was just 22, probably needed time to mature, especially in New York's withering spotlight.

But there's a simpler, truer explanation for why things went so wrong for him: The Jets aren't a particularly good football organization, and when it comes to coaching and overseeing an offense, Ryan is indifferent at best and negligent at worst. In those kinds of surroundings, it doesn't take much for a young quarterback to get lost.

So here is Mark Sanchez now, 27 years old, a little wiser, a little humbler, and here's another Monday night start ahead for him next week, this time against the Carolina Panthers, this time set up to succeed in a way he'd never been before in the NFL. "I once thought," an enthusiastic football fan named F. Scott Fitzgerald wrote, "that there were no second acts in American life." Forgive Mark Sanchez if, as recently as 1 p.m. Sunday, he might have thought the same thing.

@MikeSielski