When John Brantley went down when his leg was twisted in an unnatural way on a sack by Alabama’s Courtney Upshaw last week, Florida found itself in a precarious spot.

For all the depth major college powerhouse programs tend to accumulate, Florida found itself thin at quarterback. Behind Brantley, in his second year as the starter following the Heisman Trophy career of Tim Tebow, was true freshman Jeff Driskel, who looked woefully overwhelmed by the moment as the Crimson Tide ran away for a 38-10 win.

With Brantley out, the Gators continue to be in the same bind today when Driskel makes his first college start at LSU, a program that can relate to Florida’s current problem, but at the moment stands in remarkable contrast.

How does as program like Florida, which has produced three Heisman Trophy-winning quarterbacks and has a recent history of strong quarterback play, end up so thin at the game’s most important position?

You need only look at LSU’s recent history to relate. Remember 2008? After Ryan Perrilloux was kicked off the team, LSU had to turn to a redshirt freshman, Jarrett Lee, a walk-on in Andrew Hatch and, eventually, a true freshman in Jordan Jefferson.

This kind of thing is not unusual these days. Look at Texas last week where Garrett Gilbert, seeing little future with young quarterbacks taking his playing time, left the program. At a position where, unlike positions like running back and wide receiver, one guy tends to get all the significant snaps, high-level prospects don’t stick around if they aren’t going to be that guy who gets the snaps.

For Florida, Brantley was the lone veteran of the group in part because a certain rising star -- a Cam Newton -- left the program a few years back. Last year’s QB prospect, Trey Burton, was moved to running back. Just like that, you’re down to a true freshman on the second team.

But you’ll be surprised how often that kind of thing is the case in the major college landscape.

Of course, there are exceptions, including one lining up against the Gators today.

We might quickly forget that LSU will also start the guy who started August camp as its No. 2 quarterback.

But Jarrett Lee is no wide-eyed redshirt freshman anymore. He’s a senior who has started games before, led wins, and heard the boos from that painful 2008 season.

He’s seasoned, mature and confident. And conventional wisdom says he has no business still being at LSU.

And he’ll be backed up today by the guy who was the starter, Jordan Jefferson, the guy who lost his job after a messy barfight got him caught in the legal system in the season’s infancy. No problem, LSU simply plugged in Lee to win five straight, including three against ranked teams away from home, to start the season.

And it’s not just Lee. LSU’s been banged up this year, but it’s had veterans to turn to when needed.

When guard Josh Dworaczyk was lost for the season to a knee injury in August camp, senior T-Bob Hebert was there to take his place. When tackle Chris Faulk was, to borrow a Les Miles term, “nicked,” he was competently replaced by senior Greg Shaw.

Against Kentucky last week, the Tigers were able to go deep into their stable of running backs to pull out Alfred Blue, a sophomore who, after falling behind fellow sophomores Spencer Ware and Michael Ford on the depth chart, didn’t sulk. Instead, he played special teams exceptionally well, and when his number was called last week, responded with a career-high 72 yards on 16 carries.

If you ask me, that’s one of the hidden secrets to LSU’s success this season.

Miles and his staff have done a good job keeping players who aren’t necessarily on path to be stars engaged in the program. It’s very easy to imagine players like Lee and Shaw playing elsewhere right now.

Instead, they’ve started games, and performed, for the No. 1 team in the country.