Editor's note: NBC broadcasters will offer opinions on upcoming races the remainder of the season. This week, analyst Jeff Burton discusses Saturday's NBCSN presents NASCAR Sprint Cup Racing from Bristol Motor Speedway immediately following the conclusion of the men's soccer gold medal match Saturday, about 7:30 p.m. ET.
Jeff Burton has seen change at Bristol over the years. But as he looks to the Sprint Cup racing at the track this weekend, he says nobody knows what will happen.
He does, though, expect a return to "old-school Bristol." The half-mile track was once loved and hated for its rough-and-tumble racing, for the ability to watch a solid run disappear in a moment's touch of a bumper.
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In recent years, changes to the track made it more possible for drivers to pass without contact. Now though? The track has seen changes once more in an effort to get the bottom groove to work better.
And that throws much out the window.
So what does Burton expect to see in Saturday night's race?
"I have no idea," said Burton, a former driver and current NBC analyst. "With the changes that the track made with polishing the bottom groove, then running the tire dragging over it and putting the treatment on the racetrack trying to get the bottom groove to come in — like (in Wednesday) night's Truck race, the bottom groove was the preferred lane, but you saw late in the race William Byron made a move on the outside and made that work. I don't know if that was because that was … the bottom groove was starting to wear out or if the truck in front of William's was that much slower than William. I don't know."
Rain throughout this weekend could continue to wash rubber off the track, perhaps further complicating things.
The track had major changes in 2007, with resurfacing and widening of the turns. Then, as Burton points out, drivers had tested on the track and had an idea what was going to happen.
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Now?
"Going into Bristol this race, I don't know of a time that there's been more unknowns," he said.
As he watched the Camping World Truck Series practices and race earlier this week, Burton seems amazed by what he saw.
"I watched both practices and in the second practice people started running the bottom groove and they were picking up over half a second from the bottom groove," he said. "Half a second, in racing terms, at a half-mile racetrack is astronomical. A half a second is an unbelievable amount to pick up. So if that bottom groove becomes the preferred groove, then we're in store for an old-school Bristol race where everybody's racing for the bottom and you know what happens with that. When there's only one groove, and you have to run the bottom, there's a lot of pushing, a lot of shoving, a lot of caution."
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Therefore, he says, drivers must enter this weekend with an open mind. They'll watch Friday night's Xfinity race, waiting to see what will happen.
That, too, could raise issues. Say, for example, the bottom lane is faster all day Friday. And then in the Xfinity race, the top lane improves. Now what?
"That's where it gets really hard," Burton said. "… Many times you go to Bristol and in practice people are running three-quarters of the way up top but they're not running against the wall because in practice there's not enough rubber to run against the wall. But in a race you immediately get up there. So think about for a driver, for a team, what happens if you only run the bottom in practice and in qualifying. And then that wears out and changes and now you're running the top three-quarters of the way through the race.
"That's almost going to be luck. That's almost going to be, 'Our setup worked better at a slower pace on the top than it did on the bottom.' It's going to be hard to have those. It's going to be very difficult, if the track changes that much, for the car that's the fastest in the bottom lane to still be the fastest in the top lane. That's going to be a very difficult thing to pull off."
That could have huge implications for the Chase as well.
Dodgy conditions could create the opportunity for "strange things to happen." That's good if one needs something big, like a win, to break into the Chase for the Sprint Cup.
If what one needs, though, is just points, then things could get more complicated.
"For those teams that need points, you look at Jamie McMurray, you look at Chase Elliott, Ryan Newman, (Austin) Dillon, you look at those guys, they're nervous as hell," he said.
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Burton understands the nuances of racing at Bristol. A winner there, he sees a vast difference in racing at the top and racing at the bottom.
"The Bristol where the groove is on the top is way calmer to drive, is way less hectic," he said. "You don't feel G-forces like you do on the bottom when the bottom is better, things don't happen as quickly, you have an escape route, when somebody has a problem you can go underneath them. It's easier to manage when the groove is on the top. I'm not saying it's easier to pass, it's not easier to pass, but it's easier to manage 500 laps.
"When the lane is on the bottom and you only run the bottom, it's much harder to manage 500 laps because so many more things happen that are out of your control and you don't have escape routes and it's easier to get in a wreck."
While there are numerous unknowns entering the weekend, Burton is certain of one thing — that this race should continue what fans saw recently at Pocono and Watkins Glen. In those races, drivers fought hard for positions, passing all over the track and going all-out to earn the best finishes that they could.
"The races since Indy have been really, really good," he said. "They've been fun to watch, they've been exciting, they've been a lot of things happening, they've been crazy and I expect that to continue Saturday.
"Saturday night is going to be just as interesting and crazy as the two races prior to it."