ATLANTA — Thanks to a late turnover by Virginia Tech, Duke escaped with a narrow win Friday night, but the 60-56 win raised as many questions as it answered for the Blue Devils.

Namely, who knew Ryan Kelly was so important to Duke?

Sure, the 6-foot-10 forward from Raleigh can stretch defenses with his 3-point shooting ability, and he's averaging 11.8 points and 5.4 rebounds, but it turns out his mere presence in Duke’s forward rotation is absolutely and unquestionably essential. The rest of it is a bonus.

With first Mason Plumlee and then Miles picking up early fouls, Krzyzewski used Josh Hairston liberally and resorted to a four-guard lineup for large portions of the game. (Micheal Gbinije, the presumed fourth option, never got off the bench.)

That let Virginia Tech hang around right to the finish. The Hokies had the ball down four with 26.4 seconds to go, but their turnover turned into an Austin Rivers and-one at the other end, all but sealing the win for Duke.

Perhaps more damaging, with the weakened forward rotation, Duke had to look outside for offense even more than usual, which ended up with an unusual result: A team-high 13 3-point attempts for Tyler Thornton, who made, uh, three. As a team, Duke went 5-for-26 from international waters while the two Plumlees and Hairston combined for 19 points.

That’s one thing against a team like Virginia Tech, which has a short bench and isn’t the biggest team in the world, but the situation will be completely different tomorrow, no matter the opponent.

Miami has Reggie Johnson and Kenny Kadji; Florida State has Bernard James and a cast of thousands. Whether it’s fouls to give, inside offense or sheer bulk on the boards, either team will have a significant advantage on Duke sans Kelly.

It was easy to guess that would be the case going into Friday’s game, but the narrow escape against the Hokies confirmed the worst-case scenario: The Blue Devils are going to have their hands full.

DeCock: twitter.com/LukeDeCock or 919-829-8947