CHAPEL HILL, N.C. (AP) North Carolina coach Larry Fedora sees his team making plenty of mistakes, even after a pair of last-second wins that vaulted the 17th-ranked Tar Heels back into the national rankings .
He's trying to figure out how to fix them entering Saturday's game against No. 25 Virginia Tech.
''If we can ever get that accomplished, you would see some fireworks out there,'' he said. ''It would be pretty dang good. And that's the potential of this football team.''
That's the balance for Fedora. His Tar Heels (4-1, 2-0 Atlantic Coast Conference) sit atop the league's Coastal Division after rallying to beat Pittsburgh and then-No. 12 Florida State with scores in the last 5 seconds each time. But UNC is still spotty on defense, while the offense that has the potential to sprint past anyone still has moments that Fedora wants to clean up.
Against the Seminoles, for example, it was Elijah Hood's fumble near the FSU goal line. Fedora said there was some ''gloom'' when coaches reviewed film of a thrilling win.
''Everybody knows you can't keep living on the edge like that,'' Fedora said.
The Hokies (3-1, 1-0) are coming off a bye week and bring a tough defense to face UNC's rolling offense. Virginia Tech's offense, a faster-tempo scheme brought by new coach Justin Fuente from Memphis, has been particularly sharp in the last two games, rolling to 103 points in lopsided home wins against Boston College and East Carolina.
Virginia Tech is making its first appearance in the AP Top 25 this season, setting up the first game between two ranked teams at UNC's Kenan Stadium since 2008.
''It's great for our fans to take pride in and get excited about,'' Fuente said. ''It may add to more fanfare on the outside about the upcoming games, but it's not something that we draw a lot of focus on.''
Here are things to know about Saturday's Virginia Tech-North Carolina game:
STOPPING THE PASS: UNC quarterback Mitch Trubisky has three straight 400-yard passing games and is yet to throw an interception this year. Meanwhile, receiver Ryan Switzer enters with a two-game ACC record of 30 catches in the Pitt and FSU wins, prompting Trubisky to say that it sometimes seems ''it's just me and him out there playing catch.'' But the Hokies' defense led by longtime coordinator Bud Foster ranks ninth nationally by allowing 264.3 yards per game and 10th against the pass.
HOKIES' ATTACK: Virginia Tech's offense is taking shape. The Hokies have scored at least 36 points in every game, the outlier coming when they lost five fumbles in a 45-24 loss to Tennessee. Junior college transfer Jerod Evans has started all four games, throwing for 13 touchdowns with just one interception.
DEFENSIVE CONCERNS: The Tar Heels are still up and down on defense. They struggled for three quarters against Pitt before coming up with two straight three-and-outs in the fourth quarter to set up the comeback win, then held FSU to 14 points through the first three quarters before giving up 21 in the final quarter. ''The players know it, and we are very adamant about getting those (mistakes) cleaned up,'' defensive coordinator Gene Chizik said. ''It's about time we do it, right?''
TELLING STRETCH: The Tar Heels are seeking to become the first repeat Coastal champion since the Hokies did it from 2010-11. This will be the third game in a critical four-week stretch that could put them in control of that race, assuming they can win Saturday and then again at No. 10 Miami next week.
WEATHER CONCERNS: Hurricane Matthew has been moving north since early in the week. That could affect game conditions with wind and rain, depending on the course the storm takes as it continues its trek into Friday evening.
AP Sports Writer Hank Kurz in Richmond, Virginia, contributed to this report.
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