Virginia Tech cornerback Antone Exum tore his ACL, lateral and medial meniscus and suffered a bone fracture in his right knee while playing pickup basketball on campus. (Don Petersen/AP)

In the days after he underwent microfracture surgery to repair his right knee last winter, Virginia Tech cornerback Antone Exum would lay in bed on his computer, scanning the Internet for other athletes who suffered an anterior cruciate ligament injury and how long it took them to return.

A lifelong Washington Redskins fan from outside Richmond, Exum took solace in the success stories, such as the faster-than-expected rehabilitation of quarterback Robert Griffin III or the comeback authored by Minnesota Vikings running back Adrian Peterson last season.

With that in mind, Exum made it clear he would return in time for Virginia Tech’s season opener against two-time defending national champion Alabama on Aug. 31, just seven months after he tore his ACL, lateral and medial meniscus and suffered a bone fracture in his right knee while playing pickup basketball on campus.

But a summer spent in Arizona rehabbing alongside Tampa Bay Buccaneers cornerback Darrelle Revis and living with former Hokies running back Ryan Williams, both of whom have suffered major knee injuries in the NFL over the past two years, has persuaded Exum to dial back that stance. His injury is different than simply an ACL tear, and as Revis pointed out to him, “Don’t overdo it and just take your time and come back when you’re 100 percent and can perform like you want to.”

“I am a little bit more realistic on the time frame. Back then it was, ‘I’m gonna be back for Alabama,’ ” Exum said this past weekend at a Virginia Tech recruiting camp. “I definitely want to be back. I haven’t changed that, that I want to be back for that game. They haven’t ruled it out of the question or anything . . . but I can’t make any guarantees.”

When training camp begins next month, Exum’s availability will be one of the few question marks for a Virginia Tech defense that should be among the best in the ACC this season.

Strength, power and deceleration tests performed at Fischer Sports, a physical therapy and conditioning facility in Phoenix, revealed Exum’s knee to be about 65 percent healthy with more than six weeks remaining before the Hokies and Crimson Tide face off to start the 2013 college football season in Atlanta.

Exum, a second-team all-ACC selection who led the Hokies in pass breakups and interceptions last season, will miss the start of training camp for an Aug. 5 appointment with orthopedist James Andrews, who performed his surgery on Feb 5. Andrews must first clear him in order to return to practice.

“He’s further along than I thought he would be,” Virginia Tech head trainer Mike Goforth said of Exum. “These guys are Lamborghinis before they get hurt, and they get back to being Lamborghinis. They just got a better base to work on than we have.”

Exum is already back on the football field, performing cone drills and backpedaling on grass during multiple daily workouts. He also has proven capable of running 110-yard sprints with the Hokies’ offensive linemen.

But for a player who relished extra late-night training sessions, the pace of the recovery can be excruciating at times.

“He’s relentless. It’s to the point that: ‘You might want to let your knee rest a little bit. It’s supposed to be rehab,’ ” defensive end James Gayle said. “I wouldn’t be surprised if we had a game in three weeks and they put him out there [with] his work ethic and the way he’s been working to come back.”

Goforth noted many players dealing with an ACL injury can play after six to eight months but don’t feel completely comfortable again for another year. It’s a concept Exum is trying to embrace, even if it means easing off the throttle a bit more on his sports car these days.

“I’ve learned that there is merit in taking your time,” he said. “Just being around a lot of pro athletes out there, you learn that sometimes you need to give your body a rest.”