On top of the technical issues NFL scouts have with Tim Tebow as a prospective pro quarterback, there's also the standard next-level complaint about "the system" -- specifically, among other things, that Tebow spent the entirety of his college career at Florida taking snaps from the shotgun, never from under center, even in short-yardage situations. That seemingly minor qualm opens up an entirely new avenue of doubts about his ability to adjust to basic mechanics like footwork and turning his back to the defense, fundamentals most quarterbacks have converted to second nature long before they show up for NFL auditions (or, in most cases, before they ever set foot in an actual college game).

Florida tried to address that last year by hiring respected quarterbacks coach Scott Loeffler from the pro ranks, practicing with Tebow under center and having him take a handful of "conventional" snaps in a few games, all with an eye to making the most celebrated college player in modern history a more viable prospect to the skeptics. But when he showed up Monday for the first day of heavy scrutiny at the Senior Bowl, all the old alarm bells started ringing at maximum volume -- Tebow reportedly flubbed his first snap from center, and it only got uglier from there:

Performing drills with fellow South team quarterbacks Zac Robinson of Oklahoma State and Jarrett Brown of West Virginia, Tebow fumbled the ball at least twice while taking snaps under center.

Later in team drills, Tebow fell into his same old habits — holding onto the ball too long, locking onto receivers and throwing wobbly passes.

The scouts noticed.

"He looks like the third QB out there," one NFC South talent evaluator said.

Of course, the two QBs in front of him, Robinson and Brown, also come from shotgun-based spread schemes that featured a steady dose of quarterback-as-runner, and former Texas Tech coach Mike Leach -- as prominent an acolyte of the "college spread" as you can find -- hilariously mocked the NFL mantra when his prolific protegé, Graham Harrell, met with failing grades from the scouts last spring. ("How could you possibly look yourself in the mirror and consider yourself an NFL coach and not be able to teach a guy to run back three steps, five steps and seven steps? I can teach a child that!") Longtime coach and quarterback guru Marc Trestman, who worked with Tebow to prepare for this week, said he didn't think Tebow looked bad enough to hurt himself; Miami Dolphins coach Tony Sparano, overseeing the South roster, said Tebow improved over the course of the practice. If nothing else, he's already well on his way to replacing Brett Favre's spot in Peter King's heart in the league's most influential weekly column.

But for a guy who needed a knockout week, the initial reviews are unadulterated fuel for the haters. Handling the snap is supposed to be the easy part of the transition; if he's still struggling with the basic exchange on national television this Saturday, we won't be hearing the end of it anytime soon.

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