Drafted in the sixth round (135th overall) of the 1969 AFL Draft out of Florida A&M, Ken Riley arrived in Cincinnati as a star college quarterback. Like so many Black quarterbacks of his era, he was immediately transitioned to defense by head coach Paul Brown. Riley embraced the position switch, transforming into "The Rattler"—a technician at boundary corner whose 15-year career in Cincinnati stood as a masterclass in durability, film study, and ballhawking precision.

Riley was not a flashy cornerback who relied on trash talk or raw, unbridled size. Instead, his former quarterbacking eyes gave him a massive diagnostic advantage. He studied opposing route combinations obsessively, allowing him to jump passing lanes, bait quarterbacks into tight windows, and secure interceptions without giving up deep leverage. His footwork was exceptionally fluid, and his sure-handed tackling made him a complete, dependable defender on the edge.

Riley made an immediate impact in his 1969 rookie campaign, snagging four interceptions. He quickly secured a starting cornerback spot and launched a remarkable 15-year run of health and consistency, recording at least one interception in each of his 15 seasons.

In the mid-1970s, Riley established himself as a top cover man. He earned Second-Team All-Pro honors in 1975 after a five-interception season, and in 1976, he again received Second-Team All-Pro recognition following a career-high nine interceptions.

Despite his staggering takeaways and lockdown coverage, Riley was famously overlooked for the Pro Bowl throughout his career—a snub that baffled voters for decades. Yet his final season in 1983 served as the ultimate mic-drop moment. At 36, Riley started all 16 games, intercepted eight passes (returning two for touchdowns), and earned his long-overdue First-Team All-Pro selection.

He retired after the 1983 season, having played 207 regular-season games—all with the Bengals—and recorded 65 career interceptions, five touchdown returns, and 18 fumble recoveries. His 65 picks ranked fourth in NFL history at the time of his retirement and remain tied for fifth all-time.

When the franchise inaugurated the Cincinnati Bengals Ring of Honor in 2021, Riley was naturally enshrined as one of four charter members alongside Anthony Muñoz, Ken Anderson, and Paul Brown. His legacy received its final, righteous validation when he was posthumously elected to the Pro Football Hall of Fame as a member of the Class of 2023.