MORGANTOWN - As well as West Virginia's defense has played in recent weeks - the entire season, for that matter - there is still that nagging concern that at any moment disaster can strike.
The nightmare scenario for the Mountaineers is giving up big plays.
Oh, sure, that's a concern for every team. Even the best defenses in the country can play lights-out perfect for, say, 68 out of 70 plays. But if someone slips or misses an assignment or just plain fails to do the job on those other two, all of that perfection can be undone.
So even as he basks in the glow of how well his defense is playing right now, West Virginia coach Bill Stewart remains cautious and concerned.
"My concerns,'' he said the day after Thursday's 20-6 win over South Florida, "are still the big plays.''
And with good reason.
No, South Florida didn't come up with any, save for a 55-yard kickoff return by Lindsey Lamar that set up a field goal. Then again, that didn't come against the defense and it was not totally unexpected. After all, WVU's kick coverage has been exceptional this season, but eventually someone was bound to uncover a crack. But it could have been worse given that Lamar a week earlier returned a kick 94 yards against Syracuse for the Bulls' only touchdown in a 13-9 loss.
But as No. 20 West Virginia (5-1, 1-0 Big East) prepares for Saturday's noon home game with the Orange (4-2, 1-1), it is difficult to be entirely satisfied even with a defense than now ranks No. 5 overall in the country in total defense, No. 4 in rushing defense and No. 3 in scoring defense. OK, so perhaps it is splitting hairs, but Stewart still had a few breathless moments while re-watching that win over USF.
"I saw one play there in the fourth quarter, [USF running back Moise] Plancher went through that hole, and they had a hat on everybody,'' Stewart said. "[WVU safety] Eain Smith stumbled. If Eain Smith doesn't make that tackle - he barely cut the legs out - if he doesn't make that tackle, it's a touchdown.
"Now the game is 20-13 with a chance for an onside kick or for us to muff something or make us punt.''
That it didn't happen, of course, is the difference between a good defense and a bad one, but recent history suggests that those plays can still happen at the most inopportune moments. And even though the Mountaineers are ranked No. 11 in the country in total pass defense (and No. 22 in pass efficiency defense), the prospects for a big play remain.