ATHENS — Georgia football is chasing Alabama and Clemson in the race to establish itself a national championship program, and nowhere is the gap wider than on the defensive line.

The Bulldogs, quite simply, have not played at the same level as the Tide and Tigers and that has ultimately cost them championships.

Georgia coach Kirby Smart knows better than anyone it starts up front and that the first key to success on defense is stopping the run.

Smart’s fourth year has arrived, full recruiting cycles behind him, and the UGA defensive line still has questions and threatens to be the Achilles heel.

Smart hired Tray Scott away from North Carolina to replace Tracy Rocker two years ago.

But Scott’s relatively meager $50,000 raise and $470,000 salary — lowest on the defensive staff and $430,000 less than O-Line coach Sam Pittman — leaves room to speculate about his job approval rating.

Rocker, it’s worth noting, was making $525,000 on Smart’s staff before splitting from Georgia and going to Tennessee, where he makes $500,000.

The big question: Can UGA build the sort of line that will prevent teams like LSU from converting 4-of-4 on fourth downs and running for 275 yards in a big-time matchup?

The answer could determine whether the Bulldogs clear the Alabama hurdle and win a national title during Smart’s tenure.

Here are three more questions about the D-Line entering spring drills:

How overweight is DL Jordan Davis?

Smart indicated during an offseason radio interview that 2018 Freshman All-American Jordan Davis has weight issues, despite working with Georgia’s celebrated strength and conditioning staff.

RELATED: Jordan Davis expected to be cleared for spring drills

“Weight is always going to be a struggle and a fight for (Davis), so when you say you’ve seen him and he’s ready to play, I don’t know if you’re seen him lately but he’s got to be ready to play,” Smart told Atlanta radio station 680 The Fan in an exclusive interview. “He’s got to control his weight. He’s done a really good job of having weight discipline thus far in his career, and he’s got to continue to do that.”

Davis’ emergence provided a noticeable boost for the Georgia defensive line, which had struggled to replace 2017 senior John Atkins.

Two-gap, too much?

Smart’s preferred alignment is the 3-4, but do the Bulldogs have the sort of dominant linemen required to play the scheme effectively?

Georgia closed last season allowing five consecutive opponents to rush for more than 100 yards  — yes, UMass — and Texas rolled for 178 in the season-ending 28-21 Sugar Bowl loss.

Graduate transfer Jay Hayes from Notre Dame was supposed to bolster the defensive line in 2018, but he was unable to excel in Georgia’s system, making just three tackles with no sacks in 11 games last season.

UGA rising seniors Julian Rochester (6-foot-5, 300 pounds), Michael Barnett (6-4, 304), Michail Carter (6-3, 295) and Tyler Clark (6-4, 300) combined for just 2 1/2 sacks and 6 1/2 tackles for loss last season.

By comparison, Alabama’s Quinnen Williams had 8 sacks and 19.5 tackles for loss — himself!

Clemson’s Christian Wilkins was another one-man wrecking crew, posting 6 sacks and 15 tackles for loss.

Why can’t Georgia have a defensive lineman like that?

Breakout candidate?

Georgia football recruiting doesn’t often miss the mark, but if there’s an area where the Bulldogs have fallen short, it’s on the defensive line.

Consider, 2019 signee Travon Walker is the first 5-star defensive line catch for Georgia during Smart’s tenure.

Part of the challenge here is UGA didn’t sign any defensive tackles that enrolled in the 2017 class, and in 2018, only two of three signed defensive tackles enrolled — Davis and Devonte Wyatt.

The bet here is junior Malik Herring (6-3, 280) could be the breakout defensive lineman.

More Georgia football spring 2019

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Kirby Smart provides preview on young receivers 

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