Hoover (20-7) will next face Great Oak in a second-round game at 7:30 p.m. Tuesday at a site to be determined.
"We did our homework and we studied a lot of film on Charter Oak," said Hoover Coach Vigen Jilizian, who picked up his first postseason win since taking over the program in 2003. "We had an idea of the things that they would do and we knew that we had to be as prepared as we could be.
"We talked at practice that we had a good year win-wise, but we wanted to also win a playoff game."
Hoover stalwart senior center Zareh Zargaryan finished with a game-high 32 points. It's the most points that Zargaryan has scored in a postseason game.
Zargaryan, who also had eight rebounds, five assists and two blocks, got plenty of help from his teammates.
Hoover finished with seven steals and forced Charter Oak (13-16) to commit 12 turnovers. The Tornadoes, who finished second in the Pacific League behind Pasadena, led the entire game.
Zargaryan, an All-Area first-team pick last season, got things going early. The 6-foot-6 center had 14 first-quarter points, but didn't score in the second quarter.
He regrouped in the second half, finishing with 18 points.
"I want to push us as far as we can go," said Zargaryan, who made four three-pointers in the second half. "We knew we had to tighten up our defense and stick to our game plan because we have worked too hard to just go out in the first round."
Hoover received 16 points from senior guard Artash Davtyan and eight points and seven rebounds from senior forward Raymond Beginyan. Teammate Shara Davoodi, a junior guard, notched six points and a game-high six assists.
Junior forward Joey Mesropian led Charter Oak, which finished second in the Miramonte League, with 16 points, seven rebounds, four assists and three steals.
CHARLES RICH covers sports. He can be reached at (818) 637-3228 or by e-mail at firstname.lastname@example.org.