The senior has seen it happen firsthand.
Byrn was redshirting in 2010 when the then 13th-ranked Hokies hosted another FCS opponent, James Madison, just five days after playing Boise State on a Monday night. The Hokies led 16-7 before the Dukes scored twice and pulled off a stunning 21-16 upset.
''It was raining, it was cold and I think I left before the game was over just kind of naturally thinking that we would pull it out, and obviously we didn't,'' the redshirt senior said this week. ''That's a feeling that you don't ever want to have. The younger guys, it's easy for them being at a prestigious program to hear that and just kind of scoff at it and say `Yeah, that won't happen. Don't worry.' But it's our job as older guys and as leaders to make sure that they know.''
For some Hokies, concern about the opener, and focus, goes back to January. That's when defensive tackle Luther Maddy said he overheard some teammates talking about Ohio State. The Hokies will travel to Columbus, Ohio, next weekend to take on the fifth-ranked Buckeyes.
''I quickly responded with, `You can't overlook William & Mary,''' Maddy recalled. ''I think a lot of guys understand.'' The team's seniors, he said, ''had a team meeting for all the players and we spoke to them about our expectations for this season and we told them it all starts with William & Mary.''
A look at recent history bolsters that point.
The Tribe is entering its 35th season under Jimmye Laycock, and has made a habit of putting a scare into FBS opponents. William & Mary beat Virginia 24-16 to open the 2009 season, and held second-half leads in narrow losses against Maryland, North Carolina and West Virginia in the last four years.
''It's a matter of having good teams and playing well and not beating yourself and putting yourself in a situation where, if they mess up a little bit, make some mistakes, then you can be in a position to take advantage of it,'' Laycock said. ''... You've got to have breaks. You've got to have things go your way.''
Much like the Hokies, the Tribe will arrive at Lane Stadium with a stout defense that last season was among the best at the FCS level, and with a new quarterback and some questions to answer on offense.
Hokies coach Frank Beamer, entering his 28th season, and Laycock are longtime golfing buddies, and the longest-tenured head coaches at the FBS and FCS levels, respectively. They didn't get to make their annual trip to Augusta, Georgia, this summer, Beamer said, and he knows what he's up against.
''I think when you look at what happened at West Virginia last year, it's tied up, going late into the ballgame,'' he said. ''North Carolina a couple years back, close ballgame, very close. So they play these games a lot. They've played well in them. They certainly have got our attention and respect.''
''They're an opponent that can come in and beat you at home,'' he said. ''That's the mindset that we have to have going into this one.''
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