Armstrong hit Demick Starling on a 65-yard scoring pass and Ra'Shaun Henry from five yards out. It was Henry's fifth touchdown in eight catches at Virginia.
Freshman Darius Wilson started at quarterback for William & Mary in place of Hollis Mathis, still recovering from shoulder surgery, and got a rude welcome to the college game. He completed nine of 15 passes, but for just 83 yards, and ran for 29 yards on six carries. The Tribe managed just 183 yards.
''Darius' first start against an FBS team, you've got to give him some credit,'' Tribe coach Mike London said. ''There's some things he's got to get better at and we've got to help him to make sure he uses his arms and his legs.''
Armstrong, who scored on runs of 2 and 3 yards, completed 20 of 30 attempts for 336 yards. The Cavaliers finished with 545 total yards.
''He's a veteran quarterback that knows their scheme and knows their system,'' Tribe coach Mike London said of Armstrong. ''I knew he was a good football player and he proved it today.''
It was the Cavaliers first shutout since they beat South Carolina 28-0 in the Belk Bowl at the end of the 2018 season.
''We did a really nice job with our perimeters and our depth and so everything was inside and in front and we tackled well for an opening game,'' Virginia coach Bronco Mendenhall said. ''We didn't tackle much in fall camp and working to keep our depth as healthy as possible for a long season. And so that was a little bit of an unknown, except we had experienced players.''
Virginia started slow, twice failing to convert on fourth-down short-yardage situations, but Armstrong's first scoring run nine minutes before halftime got them started. He hit Henry in the left corner of the end zone with 32 seconds left in the half. His pass to Starling broke the game open in the third quarter.
''I think the first half, I was trying to push the tempo and in my mind, I was pushing it,'' Armstrong said. ''I was just moving a little too fast.''
The defensive effort was especially appreciated until the offense got untracked.
''You know, they said they're going to try to get a shutout every week and they did that,'' Armstrong said. ''And so it takes a lot of stress off us.''
William & Mary: The Tribe has all its starters back from last spring, when they finished 1-2, but three were absent from the lineup because of injury, including Mathis, a dual threat. Coach Mike London said this week Mathis would be a game-time decision, but also that he didn't want to rush him back and risk losing him for the season.
Virginia: The Cavaliers registered only one sack against Wilson, although they had him scrambling quite a bit, and preserved the shutout when Nick Grant blocked a 36-yard field goal try by Ethan Chang.
William & Mary opens its home season against Lafayette on Saturday.
Virginia remains at home to face Illinois of the Big Ten next Saturday.
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