Richardson made a team-high 100 receptions in 1967 and 1968, when Baltimore went 24-2-2. He made the Pro Bowl both years. In Super Bowl III — an upset loss to the New York Jets — he was one of the few Colts who stood out, with six catches for 58 yards in a 16-7 defeat.
"Willie was a good, good athlete," said teammate Lenny Moore, a Hall of Famer. "Hearing of his loss just kicks me in the corner. I'm in shock."
The Colts' seventh-round draft pick in 1963 out of Jackson State, Richardson played behind All-Pros Raymond Berry and Jimmy Orr until 1967, when injuries sidelined Orr. Richardson stepped in and caught 63 passes for 860 yards and eight touchdowns as the Colts went 11-1-2 but failed to make the playoffs.
Orr did color commentary for a local radio station that season and approached Richardson after his 11 receptions fueled a 38-6 win over the Philadelphia Eagles.
"I asked Willie, 'Are you trying to take my job?' " Orr recalled. "Darned if he didn't. When I came back the next year, I had to move from the left side to the right."
Orr said he spoke to Richardson on Friday.
"Willie was supposed to join me for a golf tournament in Biloxi, Mississippi," Orr said. "He called and said, 'Tell them my wife is sick and I can't come.'
"Three days later, he was gone."
At Jackson State, Richardson was a two-time small college All-American.
"He was an impact player and probably the most acclaimed athlete to come out of the school," said Roy Hilton, a defensive end who also played there before being drafted by the Colts in 1965.
"A lot of people who came from 'minor' colleges were [intimidated] by playing with the likes of Johnny Unitas and Gino Marchetti — but Willie represented himself extremely well," Hilton said. "It took him awhile to learn the Colts' pass patterns, but, by the time I got there, he'd gone from a green rookie to a crafty veteran. Not too shabby."
Richardson played nine years in the NFL, eight with the Colts during which he caught 188 passes for 2,883 yards and 28 touchdowns.
"As a rookie, I saw that [Hall of Famer] Raymond Berry and Jimmy Orr never dropped balls in practice, much less in games," he told The Baltimore Sun in 2012. "Miss one pass, and you felt like you didn't belong. Those guys raised the bar for the rest of us."
In that interview, he recalled his reaction to catching a 23-yard TD from Unitas to defeat the Green Bay Packers, then the Colts' nemesis, 13-10. Richardson celebrated by throwing the football into the upper deck at Memorial Stadium.
"I'd been a quarterback in high school, so I could throw," he said. "The fan who caught the ball had me sign it, too."
Richardson retired in 1971 but remained in Baltimore to run a liquor store he owned in Pimlico. He also served as sports director at Channel 45 and coached football briefly at Johns Hopkins. In 1980, he moved to his native Mississippi and worked 25 years for the state's tax division. He also spent several years as color analyst for football games at Jackson State. In 2003, he was enshrined in the College Football Hall of Fame.