Fifteen minutes into the 2019 football season, Hawaii linebacker Darius Muasau and defensive back Steven Fiso stamped their time cards.

By playing on special teams in the Aug. 24 opener against Arizona, both true freshmen triggered their NCAA eligibility clocks and opened conversations on how they will be used this season.

“You definitely have to be strategic in how you see their roles,” defensive coordinator Corey Batoon said.

Batoon was referring to a one-year-old rule in which a player may appear in up to four games and still qualify for a redshirt season.

The Rainbow Warriors took advantage of the rule in 2018 when quarterback Chevan Cordeiro, defensive back Kai Kaneshiro, kicker Michael Boyle and defensive end Jonah Laulu maintained their freshman status after each played in four games. In all, 14 Warriors redshirted after playing in games in 2018.

But because of pressing needs, left tackle Ilm Manning, right guard Solo Vaipulu, nose tackle Blessman Ta‘ala and safety Khoury Bethley played in all 14 games as true freshmen last year.

With Penei Pavihi recovering from a season-ending knee injury, Muasau moves into the linebacker rotation for Saturday’s game against Oregon State. Barring injury or the emergence of another linebacker, Muasau probably will be needed to play the rest of the season.

With depth in the secondary, Fiso might fit into the four-game limit this season. It is likely freshman safety Tiger Peterson, wideouts Jonah Panoke and Mekel Ealy, and slotback Lincoln Victor will be sprinkled into four games.

“You try to figure out how you’re going to use it,” head coach Nick Rolovich said of the redshirt rule. “We have to be trying our best to win football games, but also keep the best plan, as best we can, for the players and the team in the future.”

Rolovich indicated the possibility of playing has served as an emotional carrot for redshirt candidates during practices. Prior to the rule, Rolovich said, “you tell them, ‘oh, you’re redshirting,’ then they check out and cruise through practice.”

Batoon said: “Being engaged, understanding, learning, knowing you might have an opportunity to play this week, helps the kids stay motivated.”

As a first-year Warrior in 2018, Cordeiro prepared as if he would be the starter each week. “I’m always locked in,” said Cordeiro, who played in four games, starting one, last year “I don’t want to be the guy playing around on the sideline and then being called. I want to be ready.”

Kaneshiro exited the 2018 training camp as the No. 2 strong safety. He played in the opener, but then others emerged as safeties and special-team players.

“Maybe midway through the season, that’s when the complicated talks started,” special teams coordinator Michael Ghobrial said. “Should we redshirt this guy or is he going to play a lot more? A guy like (Kaneshiro), you wanted to save the year but still have the ability to play four games, which he did.”

Kaneshiro said: “I didn’t really take it like I was redshirting. I took it like, ‘This is my freshman year. Whatever game they need me, I’ll go in.’ It so happened I ended up using only four games. I was blessed. It got me prepared for the game speed.”

Rolovich noted the redshirt year is not limited to true freshmen. Offensive lineman Gene Pryor played in two games last season after transferring from a junior college. He now is the Warriors’ No. 1 right tackle, with two seasons of eligibility remaining.

“You don’t have to redshirt your first year,” Rolovich said. “There’s not a rule on that. You can redshirt your third year. Look at Penei. Thank goodness he’ll have two more years after this injury. Examples like that, also things where people look at, ‘OK, there are plenty of options on this redshirt deal.’ ”