HONOLULU (AP) -- Tyler Graunke started as a freshman in 2005 against two-time defending champion Southern California. But Colt Brennan also played that game, and Graunke wouldn't start another game until Saturday night.
Graunke overcame a rough start in place of Brennan, throwing for 285 yards and three touchdowns and leading No. 19 Hawaii to a 66-10 victory over Charleston Southern.
"I wasn't really hitting my targets but I finally settled down when the coach told me I could do it," he said.
Brennan, sidelined with a sprained right ankle, suited up and participated in warmups but sat out for the first time in his career with the Warriors.
C.J. Hawthorne had five receptions for 91 yards and two TDs for Hawaii, which improved to 4-0 for the first time since 1988 and has won 14 of its last 15 games.
Graunke had a shaky start, throwing an interception on the first play of the game and badly missing receivers. He was even booed after throwing five straight incompletions that led to two punts.
"When I'm out there, I'm in the zone. I didn't hear any fans booing. I didn't hear anything going on," Graunke said, adding that he expected to start "a little shaky," since it had been so long since he last started.
With Hawaii's high-octane offense sputtering and leading only by a touchdown midway through the second quarter, the crowd began chanting, "We want Colt! We want Colt!" But Graunke managed to get going with the help of big plays from the defense and special teams.
Ryan Mouton returned the second half's opening kickoff 90 yards to give Hawaii a 28-10 lead. A minute later, linebacker Adam Leonard intercepted an errant pass by Eli Byrd and returned it 36 yards for another score.
Hawaii's aggressive defense pressured Byrd all night, sacking him four times and forcing four turnovers. Byrd was 13-of-31 for 184 yards with two interceptions. He also had 30 yards rushing on 10 carries.
Graunke finished 22-of-36 and hit Hawthorne for a 35-yard score to put Hawaii up 49-10. He also had a 6-yard TD run, set up by a 27-yard interception return by Desmond Thomas that gave Hawaii the ball at the Charleston Southern 8.
Leading comfortably, Graunke was replaced by third-string quarterback Inoke Funaki, who threw for a pair of fourth-quarter touchdowns.
Brennan was injured last Friday but still played against UNLV, leading Hawaii to a 49-14 win. An MRI exam revealed no serious damage, but he spent most of the week on crutches.
Warriors coach June Jones said Brennan could have played but didn't want to risk further injuring the ankle.
"I could tell he was ready to play and wanted to play but I just told him I'm not going to play you unless we need you," he said.
In three games, Brennan has completed 77 percent of his passes for 1,262 yards and 12 touchdowns, against only one interception.
Jones said all wins are good, but called this one "ugly."
"That's because our expectations are higher than they have ever been," he said.
The Buccaneers (1-3) put up a strong first-half effort, considering this was their first game against a ranked opponent and they were 4,750 miles from home.
"We came to win. As a coach you do your team a disservice if you don't have that as a goal," Charleston Southern coach Jay Mills said. "We need -- to play at the level we want to play at -- raise the bar. This certainly was a team that allowed us to raise the bar."
The Bucs tied the game at 7 late in the first quarter on a 57-yard pass play from Byrd to Dee Brown, who caught it near the Hawaii 40 and broke free from the cornerback -- bringing the few dozen CSU fans to life.
Nick Ellis' 48-yard field goal cut Hawaii's lead to 21-10 at halftime.
The Bucs were the second Football Championship Subdivision (formerly known as Division I-AA) opponent for Hawaii. The Warriors opened the season with a 63-6 victory over Northern Colorado.