"It's a chance for a new beginning now," says Riley, who dazzled Golden Knights fans with more than 1,300 total yards, 15 total touchdowns and more than 60 tackles during his senior season. "Now I get to show off what I've been preparing for all my life."
Despite the warm weather, with a camera clicking away, Dietrich insists on putting his Golden Knights letterman jacket on, as he pulls it on over a UCLA T-shirt, sure to pay homage to his past and his present all at once.
His future is on the doorstep, the week ahead will bring him newspaper clippings about standout performances in scrimmages.
But before that, he stands in front of a quiet St. Francis High that he called home for the past four seasons, the last of which saw him lead the Golden Knights to a 9-3 record and the second round of the CIF Southern Section Western Division playoffs.
He was a four-year varsity standout, an All-Area and All-Mission League selection as a freshman.
He received his first scholarship offer, coming from Pete Carroll and USC, shortly after his sophomore season.
Having showcased his overall athleticism with seasons on the basketball and track and field teams and even dabbling in baseball for a time, his true talents and versatility played out on the football field.
Whether it was as a safety, where he will play at UCLA, as a linebacker, as a running back or a receiver or even lining up at quarterback, Riley was a difference-maker, a game-changer, an impact player and then some.