Virginia Tech cornerback Brandon Facyson may miss Saturday’s game against Duke with a concussion. (John Bazemore/Associated Press)

Just when it appears Virginia Tech will finally get back its best cornerback from a year ago, the Hokies could be without their most prolific defensive back from this season on Saturday against Duke.

Cornerback Brandon Facyson, who currently has more interceptions (four) than any other freshman in the country, suffered a concussion in practice Sunday, and “it’s too early to tell” if he’ll play against the Blue Devils, according to head athletic trainer Mike Goforth.

Facyson was in a green, no-contact jersey during Tuesday’s practice. He was injured after intercepting a pass by quarterback Logan Thomas in a pass skeleton drill and landed awkwardly while being tackled by tight end Kalvin Cline.

“I came down and my neck snapped back and I hit the back of my head on the ground,” Facyson said. “So got up feeling a little woozy, took a couple plays off and that’s when I knew something was wrong. I wasn’t in my right state of mind.”

Defensive backs coach Torrian Gray said Facyson will be evaluated as the week progresses, noting that “I’ll be more concerned if he doesn’t practice” Wednesday.

It’s the first concussion of Facyson’s football career.

“If I’m ready to play, I’ll definitely go at it. But if I’m not, I don’t want to jeopardize myself,” Facyson said. “We have many great DBs here, so they’ll take up the slack. It’s kind of judging on how I feel. . . . Honestly, I just want to make myself feel better. I want to be 100 percent before I got out there and risk anything else.”

Even if he’s healthy enough to play, though, Facyson likely would not be in the starting lineup Saturday. Barring any setbacks, senior cornerback Antone Exum is set to make his season debut against the Blue Devils after missing the first seven games of the year as he continued to recover from offseason microfracture surgery on his knee.

Exum tore his ACL, lateral and medial meniscus and suffered a bone fracture in his right knee playing pickup basketball last January. He was cleared to play by doctors earlier this month, but sat out the past two games as a precaution.

In 2012, Exum finished with an ACC-high 16 pass break-ups and a team-high five interceptions, including one in each of the final three games of the year. He was named MVP of the Russell Athletic Bowl and later explored entering last year’s NFL draft.

“I’m pretty positive Exum’s gonna go,” Gray said. “I know he feels excited. He’s gonna start the game and we’ll evaluate him from there and see where he goes. But he’s definitely prepared mentally and physically to start the game here.”