He can change the outcome of a play by using a burst of speed. He can anticipate where a quarterback intends to throw as if reading his mind. He can inject himself into a play by coming out of nowhere to make a tackle.
Bob Johnson said.
A year ago, Mascarenas was a sophomore starter who opponents often tested because he was 15 years old and supposedly lacking in experience.
All he did was come up with eight interceptions and become the only sophomore selected to the Pac-5 Division all-star team.
This season, the 5-foot-11, 175-pound Mascarenas has more speed, more strength and is ready to create more havoc on defense. He had 10 tackles in Mission Viejo's 26-22 season-opening victory over Cincinnati Moeller in Ohio on Saturday.
His athleticism is something to admire. He started at second base for the baseball team and averaged close to 20 points a game when he played freshman basketball. His sister, Toni, was a three-time All-American softball player at Arizona.
He thrives on challenges and isn't afraid of one-on-one matchups.
"If you get beat at cornerback, everyone knows you made the mistake," he said. "I guess it helps me play better."
During the summer, Mascarenas was easy to identify in the seven-on-seven passing games. If opponents dared to throw in his direction, he'd find a way to assert himself. He had five interceptions at the Dana Point Dana Hills tournament in June.
"He's very instinctive," Johnson said. "He's very quick to react."
Mascarenas has been playing football since he was 11. He started as a quarterback.
"I like hitting people better than getting hit," he said.
Saturday morning tells Mascarenas what kind of game he had Friday night.
"Usually after every game, I'm sore," he said. "It means I was in a football game. I don't look forward to it, but I guess it's a good sign when I wake up."
What gets Mascarenas pumped up is the physicality of the sport.
"It's just knowing when you're going to get a good hit on someone, then doing it and seeing the reaction from everyone," he said. "It's fun."
Johnson never has to worry whether Mascarenas is working hard to keep improving. It's part of his makeup.
During the summer, he would work out in the school's weight room or drive to the beach to run barefoot in the sand.