Without QB Will Grier, Florida's Playoff Hopes Rest on Gators Defense

Florida's first tough loss of the 2015 season wasn't sealed in a football stadium on a Saturday afternoon—it came in a Monday press conference.

Head coach Jim McElwain announced Monday that Gators starting quarterback Will Grier has been suspended for one year after testing positive for a banned performance-enhancing substance found in an over-the-counter supplement, per Edward Aschoff of ESPN.com. 

Now Florida must head to LSU Saturday for a cross-divisional matchup of undefeated opponents without its offensive leader.

But while Grier won't suit up for the Gators in Death Valley, the rest of the players who have been key to Florida's unexpected and unbeaten start to 2015 will.

Was Grier one of the most important—if not the most important—players for the Gators as the starting quarterback? Absolutely. But he's just one player in a team game.

Florida has 10 other starters on the offensive side of the ball and numerous role players who have also made tremendous strides so far in 2015. One of the most inexperienced offensive lines in the country pushed Ole Miss around. The running backs and receivers are more consistent and explosive under a new coaching staff.

L.G. Patterson/Associated Press

And then there are those excellent Gators who line up on the defensive side of the ball—the ones who are going to keep Florida's increasing hopes of playing for a championship alive.

Florida's offensive resurgence with McElwain and Grier has been well-documented at this point. But even with a new coaching staff, an elite Florida defense has remarkably improved its averages from a top-notch 2014 under former head coach Will Muschamp.

Statistic	2014	2015
Total YPG	329.8	296.3
PPG	21.1	14.3
Passing YPG	213.6	197.2
Rushing YPG	116.2	99.1

One of the biggest surprises from the Florida defense this season has been its improvement in the pass rush despite losing first-round draft pick Dante Fowler Jr. this offseason. According to Daniel Thompson of Gator Country, the Gators are averaging more sacks per dropback than last season. 

Combined with star defensive backs such as Vernon Hargreaves III and Jalen Tabor, Florida's pass defense has been elite in 2015. But Florida defensive line coach Chris Rumph said last week that he believed the best was still yet to come from the Gators up front.

"They’re still flashing," Rumph said, per Thomas Goldkamp of 247Sports. "We still haven’t played our best game yet as a unit. We have some guys that have some good individual performances the first few games, but as a unit, we’ve still got a ways to go. Those guys have to get better, I’ve got to coach them better."

Florida will be able to lean on that success and hunger from the defensive line in the next few weeks. Before facing Georgia's Greyson Lambert and Florida State's Everett Golson later this season, the Gators must tackle the challenge of an improving Brandon Harris at LSU.

Then, of course, there's Leonard Fournette.

Rob Foldy/Getty Images

LSU's Heisman front-runner at running back and its intimidating home-field advantage—a trademark night game in Death Valley—give the Tigers a clear edge over the Gators. Before the Grier news came down Monday, Florida already opened as a 6.5-point underdog, per Odds Shark. 

As Martin Fennelly of the Tampa Tribune wrote Monday, the difference between an expected loss for Florida in Baton Rouge on Saturday and a road upset is on the defense, not the adjusting offense.

"Look, neither Grier nor Harris was going to try to tackle Fournette, not that anyone has done much of that this season," Fennelly wrote. "I think LSU was going to win this game even with Grier, despite Florida’s stout defense showing large amounts of game while shutting down Ole Miss."

The Gators have already excelled on defense against a high-powered offense for an undefeated team. But LSU is a different animal than Ole Miss, and it's one the Gators will have to hunt away from home.

And even with its statistical dominance this season, Florida's defense knows it must step up against the run after what happened the last time it faced a good rushing attack. 

Florida allowed 254 yards and two touchdowns on 51 carries to the likes of Tennessee's Joshua Dobbs, Jalen Hurd and Alvin Kamara in its thrilling comeback victory over the Volunteers.

Ed Zurga/Getty Images

Now, with Fournette coming up, McElwain is calling out his rush defense.

"We’ll see how we do in practice," McElwain said, per Zach Abolverdi of the Gainesville Sun. "We’ll see if we actually wrap up. He’s probably excited as hell right now, saying 'I may be staring at a 300-yard game against these guys.'"

How Florida's defense handles Fournette and the rushing threat of Harris will set the tone for the stretch run of the 2015 season.

Georgia might not have star running back Nick Chubb for the rest of its season, but it can still lean on talented reserves such as Sony Michel and Keith Marshall. Then there's Dalvin Cook for Florida State—the nation's No. 2 running back behind Fournette.

Judging by the challenges the Gators still have left this season, Florida's playoff push will be decided by the play of its elite defense more than its offense.

As Andy Staples of Sports Illustrated wrote Monday, Florida is currently viewed as a team playing with "house money" after its better-than-expected start to 2015. Even without Grier, the Gators have already set themselves up in good position to challenge for the SEC title.

"If backup quarterback Treon Harris and a still-ferocious defense can somehow beat LSU or Georgia... Florida would stand a strong chance of winning the SEC East," Staples wrote. "The loss of Grier represents the loss of a little of that house money—but not all of it."

If Florida is able to cash in this season, the defense will take it straight to the bank.

Unless otherwise noted, statistics courtesy of cfbstats.com.

Justin Ferguson is a college football writer at Bleacher Report. You can follow him on Twitter @JFergusonBR.