When No. 8 Virginia Tech took a 21-point lead into halftime early tonight, there were two reasons for hope among Virginia fans in the record Scott Stadium crowd--the last time these fierce rivals met and the ankle injury to Hokies quarterback Michael Vick. Both quickly were shattered and the Hokies rolled to a 31-7 victory.

In just the second full game of his career, redshirt freshman Vick was the clear star with the sort of all-around play that gives Virginia Tech (4-0) a fine chance to win its remaining games, all in the Big East, and contend for its first national championship.

Vick limped off in joy after playing the entire second half, but all that had been necessary were lots of handoffs as the Hokies' defense kept No. 24 Virginia from repeating what happened last year in Blacksburg--the greatest comeback victory in school history.

The current ranking is Tech's highest ever--and that almost surely will improve because No. 3 Florida and No. 5 Texas Tech lost.

Vick produced the first Virginia Tech touchdown with a textbook-perfect pass to swift flanker Andre Davis and set up the next three with his passes and runs. The injury to Vick was the same left ankle he sprained diving into the end zone in the season opener against James Madison that kept him out the next week. Vick played against Clemson, but threw too often into double coverage and was intercepted three times.

"We can play with anybody in the country when [Vick] is healthy," said Hokies defensive end Corey Moore. "And you can't say enough about the offensive line and the receivers. They really accept Michael Vick as a leader out there."

Virginia was lucky to have one defender close to the Hokies' wide receivers when the game was in doubt as Vick completed 6 of 7 passes for 203 yards and a touchdown in the first half. The always-strong Hokies defense mostly was excellent and assured victory midway through the second half by stopping Virginia on fourth and 10.

Said Cavaliers Coach George Welsh: "We didn't execute well on offense. We got ourselves in too many long-yardage situations. That's not our game right now."

The Cavaliers also were disorganized much too often. They were penalized three times for illegal substitutions and once had at least 20 players on the field when Virginia Tech snapped the ball on a punt before Virginia's units could make the proper transition.

Virginia Tech's chances were enhanced by the absence of Virginia's best defensive player, linebacker Yubrenal Isabelle, whose mother died earlier this week of breast cancer.

On three of its first four plays from scrimmage, Virginia Tech ran the ball inside. That helped set up the Cavaliers' defense for Vick's first long pass, one of those tight spirals that Davis caught in stride at about the 15 after blowing by cornerback Tim Spruill and coasted into the end zone to complete a 60-yard play.

Virginia got a first down on Thomas Jones's 14-yard run on the game's first play, but none for the next 12. And after Ricky Hall returned a short punt 10 yards to the Virginia 39, the Hokies quickly increased their lead to 14-0. The big play was a 32-yard pass by Vick to backup split end Ricky Hall. Vick's protection enabled Hall to break free near the left sideline and the pass was hard and true.

But the Cavaliers immediately fought back, driving 80 yards on a combination of passes by Dan Ellis and runs by Jones.

They cut Tech's lead in half when Ellis hit tight end Billy Baber in the end zone on fourth and goal from the 1.

Vick then switched on the ignition of what was becoming a Hokies point machine and drove it 80 yards for another two-touchdown lead. A 14-yard pass to tight end Browning Wynn and two option runs by Vick totaling 22 yards were the major gainers.

With more good field position, this time from their 40, the Hokies had a 28-7 lead in four plays. Once more flanker Davis beat cornerback Spruill, outleaping him at the 4 for a 50-yard gain on Vick's high heave. Tailback Shyrone Stith scored his second straight short-yardage touchdown.

A 42-yard punt return by Hall, to the Virginia Tech 48, set up the Hokies for yet another surge 71 seconds before halftime. Vick's pass to backup flanker Terrell Parham for 22 yards was the major gainer, but Vick turned his ankle after a nine-yard run to the 9. On first and goal inside the Virginia 1, reserve quarterback Dave Meyer fumbled and Virginia recovered.

That fumble may have been why Vick played the entire second half. But the Hokies' defense this time pitched a second-half shutout.

"We weren't going to run [Vick]," said Virginia Tech Coach Frank Beamer, "but we felt like we needed him in there for leadership. We let them come back last year. We weren't going to let that happen again."

Staff writer Angie Watts contributed to this report.