Florida’s College Football Playoff hopes have gone up in smoke.

Or, in this instance, maybe fog would be more appropriate.

On a gloomy evening in The Swamp, the No. 6 Gators were upset by an undermanned LSU team, 37-34. Though Florida had already clinched a spot in the SEC title game by winning the SEC East, Saturday night’s loss will almost certainly knock the two-loss Gators out of the CFP picture — even if they manage to upset top-ranked Alabama next week to win the SEC.

LSU’s defense has been carved up by SEC offenses on a weekly basis. And Saturday night was no different. The Gators racked up more than 600 yards on the evening, but were doomed by three costly first-half turnovers.

But it wasn’t the turnovers that would cost Florida in the end. Instead, it was an inexplicable mistake by the Florida defense that would ultimately give LSU the chance to win the game.

Florida tied the game at 34-34 with 2:51 to go, giving LSU a chance to go back in front in the final minutes. But it looked like LSU was going to go three-and-out instead.

In fact, the Tigers did go three-and-out until Florida defensive back Marco Wilson was flagged for unsportsmanlike conduct to give LSU an automatic first down.

What was the infraction? Wilson tossed an LSU player’s cleat down the field. For real.

The penalty gave LSU’s offense new life — first-and-10 at the 44-yard line. From there, the Tigers were able to pick up enough yardage to set up a field goal try from Cade York. It wasn’t any ordinary field goal, either.

York stepped up and drilled a 57-yarder through the fog, giving LSU a 37-34 lead with 23 seconds remaining.

Moments later, Florida’s Evan McPherson would have a chance to send the game to overtime with a long-distance kick of his own.

But McPherson’s 51-yard try sailed left, and LSU held on for a nail-biting victory.

Florida’s early mistakes prove costly

Wilson’s dumbfounding penalty is going to get a lot of the attention, and deservedly so, but the early game mistakes of Kyle Trask put the Gators into a hole.

Trask, Florida’s Heisman Trophy candidate quarterback, threw two first-half interceptions. One was returned 68 yards for a touchdown by LSU freshman Eli Ricks. The other came deep in LSU territory off of a wild pair of deflections and took points off the board for the Gators.

Between Trask’s turnovers and impressive play from true freshman quarterback Max Johnson in his first career start, LSU took a 21-17 lead just before halftime. That lead then grew to 24-17 at the break when York tacked on a field goal after an ill-advised fumble from Trask in UF’s own territory.

Florida stormed back, but couldn’t hold on

LSU’s lead grew to 27-17 midway through the third quarter, but the Florida offense finally woke up. Two Trask touchdowns, a one-yard run and a nine-yard pass to Kadarius Toney, gave Florida a 31-27 lead with 3:11 left in the third quarter.

And when the LSU offense went three-and-out on the ensuing drive, it looked like the floodgates may open. Instead, the much-maligned LSU defense forced a three-and-out of its own, giving Johnson another opportunity to lead the offense.

The freshman came through. The big play was a 41-yard connection between Johnson and fellow freshman Kayshon Boutte. The Tigers then went ahead 34-31 when Johnson connected with Tre Bradford for a four-yard score on third-and-goal.

The Florida offense has put up points at will throughout the season, but couldn’t when it mattered most. UF’s next two drives totaled seven yards, and ended with punts.

UF would tie the game with a 72-yard drive late in the fourth, but an intentional grounding penalty by Trask on first-and-goal doomed what should have been the go-ahead drive.

Instead, the drive culminated with a short McPherson field goal and opened the door for one of the wildest finishes of the season.

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