Philip Rivers remembers the exact moment when he knew his oldest son Gunner was all in on a future career in football.

“We were watching the Colts on Monday night football. He couldn’t have been more than 7,” the longtime NFL quarterback and current St. Michael Catholic head coach said. “I was in the kitchen, and he said, ‘Hey Dad, Reggie Wayne just ran a sick post corner.’

“I said, ‘Wait, rewind that.’ Reggie Wayne did indeed run a sick post corner, and that is when I knew he just couldn’t get enough of it.”

Gunner Rivers, a freshman playing for his father, just finished his first year as a varsity quarterback. He had little problem living up to his father’s large shadow. Gunner completed 229-of-362 passes for 3,077 yards and 29 touchdowns as he led the Cardinals to the first playoff berth in school history. He was intercepted just four times.

“Shoot freshman season varsity football, it was a really good first year,” Philip Rivers said. “He handled it well and all that comes with it and playing a tough 4A region schedule along with non-region Gulf Shores and McGill. Looking back at a year ago, I can see how much he’s grown and changed. I’ve seen it with all the players, but you see it a little closer with your son — just the maturity and the body changes. It’s exciting knowing we have three years left.”

Despite his success on the football field, Philip Rivers said he and his wife didn’t name their son in hopes he would follow the same path.

“It’s my mom’s maiden name,” Philip Rivers said. “My grandfather was Robert Gunner. But I always said if he ended up being able to throw it or shoot it, it would be fitting so there you go.”

The name indeed has turned out to be fitting.

Gunner said it was hard not to play quarterback after watching his dad play nearly 20 years in the NFL for the Chargers and Colts.

“I’m sure it started because I was watching my dad play all those games,” he said. “Then, when I started playing flag football, I was always the quarterback. I just kind of grew into it.”

Philip Rivers said he could see his son’s talent at an early age.

“When he was playing flag football, even then he was throwing it and kind of understanding where to go and anticipating coverage,” he said. “Some guys just have that understanding and accuracy. You can work it all day and you can improve it, but Gunner just has it. Now the challenge is continuing to get better physically and mentally and knowing as much as he can know.”

College and pro scouts questioned Philip Rivers’ delivery early in his career.

Gunner’s delivery is eerily similar.

“I guess that is just the way us Rivers throw the ball,” Philip said with a smile. “Gunner’s delivery is a little more of what you would call traditional. I remember throwing in the backyard with him and telling him to lift it up a little and him saying, ‘That’s how you do it.’ But he’s compact and he gets it out quick, and I think really in the last 20 years that is all anyone cares about anymore. They don’t care how you throw it as long as you aren’t real long or getting a bunch of balls batted down.”

Like his father, Gunner’s ultimate goal is to play in college and in the NFL.

First, he has three years left with his dad at St. Michael.

“It’s so hard to compare and think of who and what and when,” Philip Rivers said in trying to analyze his son’s potential. “I only can go off what I remember at his age. I didn’t grow up playing flag football. I was playing basketball and maybe some football in the backyard.

“He has thrown a ton more passes up to his ninth-grade year than I ever thought about throwing. He has a chance to be really good. He will be physically able, and it’s just a matter of continuing to work day-by-day and see where it goes.”