John Olerud - Wikipedia
Why don't all baseball players on the field wear a helmet? - Quora
Classic Mariners Games: John Olerud Hits for the Cycle, by Mariners PR
Why don't all baseball players on the field wear a helmet? - Quora
Chris Creamer SportsLogos.Net on X: From John Olerud's brief run at trying to be a #MLB pitcher, helmet too -- Spring Training with #BlueJays in 1990 / X
Why is John Olerud wearing a batting helmet on the field in almost every picture of him? : r/baseball
Happy Birthday John Olerud and Eric Hinske - Bluebird Banter
Why don't MLB players wear helmets with two ear protectors? - Quora
John Olerud revealed the truth behind the amazing 'Rickey Henderson story
Why is John Olerud wearing a batting helmet while fielding his position? - Quora
How Did This Happen, Volume 11: Intentional Walking John Olerud - 18 Stripes