Dardov led the Tornadoes with 12 kills, including two in the early going of the pivotal fifth game, to go along with four aces and senior outside hitter Meagan Knight added 11 kills and three aces to lead Hoover to its first win of the season.
Hoover (1-2) might have swept the match had it been able to convert on game-point when up, 24-23, in the first game and hold a 21-19 lead that disappeared under a 6-0 run in the second.
"We're giving up a lot of points, we're not playing our best," Tornadoes Coach Charles Min said. "I think if we're playing well, it usually won't be this [difficult], but we're making a lot of mistakes."
After going up, 23-21, on a kill by Knight in the third game, it looked as though the Tornadoes might blow another late lead when Alverno pulled even at 23.
But Hoover held on to score the next two points and extend the match and it kept the momentum going by taking a 15-8 lead in the next game behind a five-point service run by Andrea Ghazarian.
The Jaguars (2-6) roared back to get within one at 18-17 before Dardov served out the match on a run that included two aces and a kill by Knight to bring up game-point.
"We knew we had it," Dardov said of the team's feeling going into the fifth and final game.
The fifth game started out tight, with Alverno holding a 5-4 lead before Dardov tied the game with a kill that sparked a 9-1 Hoover run.
Shaina Barrett gave the Tornadoes a 9-5 lead with a block and the margin grew to 11-5 on an ace by Ashley McClure.
The Jaguars had a little bit of fight left, mounting a 4-0 run to fend off match-point, but couldn't pull off another late rally.
"I thought that was going to be a tough one to take care of, but they did it," Min said. "We're committing a lot of errors, but we're starting to come together."