Drafted out of Charleston High School in Charleston, Illinois by the Atlanta Braves, Royer decided to not sign and attended college instead. Royer was selected by the Oakland Athletics in the 1988 draft out of Eastern Illinois University, from where he had earned an economics degree. Before the 1991 season, he was sent by Oakland along with Félix José and a minor leaguer to the Cardinals in the same transaction that brought Willie McGee to the Athletics.
In a four season career, Royer was a .250 hitter (41-for-164) with 21 RBI in 89 games, including four home runs, 10 doubles, and 14 runs scored. He also played in the Oakland, St. Louis and Boston minor league systems from 1988–1994, hitting .270 with 72 home runs and 417 RBI in 707 games.
Royer is President of Claris Advisors, an investment advising and wealth management firm based in St. Louis.