Riley O'Brien's Strikeout Message: How a Seattle Kid Became Baseball's Hottest Closer

Riley O'Brien was sitting in St. Louis on Saturday morning, about to pitch for the Cardinals against the Mariners, when the weight of his grandfather's words hit him all over again. "Throw strikes." That was Johnny O'Brien's advice, delivered via FaceTime in the final months of the Seattle sports icon's life. Simple. Direct. Effective. Now, at 31 years old, Riley is one of the best relievers in baseball, and nobody in the Emerald City is paying closer attention than his mom, Kerri Hong, who happens to be working the Mariners' chartered flights this weekend.

From Shoreline Kid to Busch Stadium Closer

Riley O'Brien grew up in Shoreline as a die-hard Mariners fan, the same way his mom raised him. He idolized Ichiro so much he dressed up as the Hall of Famer for Halloween. But here's the thing nobody saw coming: the kid who was just 5-foot-2 as a freshman at Shorewood High School was initially reluctant to even try out for baseball. His dad, Frank, had to push him. By senior year, Riley had grown to 6-2. Now he's 6-4, throwing a fastball that's touched 101 mph this season.

His journey to the majors wasn't linear. He started at Everett Community College, transferred to the College of Idaho, and was drafted by Tampa Bay in the eighth round of 2017. He bounced around, got traded to the Reds, made a brief MLB debut in 2021, then got dealt to his childhood team before the 2022 season. Riley pitched one scoreless inning for the Mariners at T-Mobile Park against the Rays, but then spent most of 2022 and all of 2023 grinding it out in Triple-A Tacoma. Good results. No opportunity. Just waiting.

Johnny O'Brien's Legacy Runs Deep

His grandfather wasn't around to see this breakthrough, but Johnny O'Brien's fingerprints are all over it. The Seattle icon died on June 13, 2025, at age 94, leaving behind a legend that shaped the entire city. Johnny and his twin brother, Eddie, turned Seattle U men's basketball into a powerhouse in the 1950s. Both got drafted to the NBA but chose baseball instead, playing alongside each other for five years with the Pittsburgh Pirates. Johnny also spent 23 years overseeing operations at the Kingdome.

"Growing up, I would always hear stories about all the things he did," Riley said. "He seemed to have his hand in just about everything." Even at 94, Johnny would light up talking baseball with his grandson through FaceTime, making a pitching motion and telling him to throw strikes. That message stuck.

The Breakthrough That Nobody Expected

Through the first month of the season, only San Diego closer Mason Miller has been better than Riley O'Brien. His mom, approaching her 40th anniversary as a Delta flight attendant, has watched her late-bloomer son finally find his moment. "I've always told him, 'Don't compare yourself to anybody else. This is your own journey,'" Hong said. "And he's taken that to heart."

This weekend in St. Louis, she's in the stands for her son and working the Mariners' charter flights. After Sunday's series finale, she'll help get the team to Minnesota. It's the perfect convergence of family legacy and second acts done right.

This article was created with AI assistance and reviewed by Seattle On Tap editorial staff. Always verify information with official team sources.