MIAMI — Jim Kiick, the versatile running back who helped the Miami Dolphins achieve the NFL’s only perfect season in 1972, has died. He was 73.

The team announced the death Saturday.

Kiick battled memory issues in recent years and lived in an assisted living home.

The former University of Wyoming star was part of a formidable backfield that included his best friend, Pro Football Hall of Fame fullback Larry Csonka. They earned the nicknames Butch and Sundance, inspired by the popular 1969 movie “Butch Cassidy and the Sundance Kid.”

Jim Kiick helped the Miami Dolphins achieve the NFL’s only perfect season in 1972 – the first of back-to-back Super Bowl championship seasons. Associated Press file photo

Kiick (“Butch”) made the American Football League All-Star team in his first two seasons and played for the Dolphins’ back-to-back Super Bowl championship teams in 1972-73. He scored two touchdowns for the ’72 Dolphins in the AFC championship game, and also scored in the Super Bowl victory that capped their 17-0 season under Pro Football Hall of Fame coach Don Shula.

Shula died May 4 at age 90.

Kiick and the speedier Mercury Morris split playing time during the 1972-73 seasons, which gave Shula a potent one-two punch at halfback but sometimes led to second-guessing by fans.

“Kiick and Mercury Morris both contributed,” Shula said. “Every Monday there was a controversy, but the bottom line wasn’t bad.”

Csonka compounded the challenge for opponents. He and Kiick met at an all-star game the summer they joined the Dolphins, and as running mates they roomed together, partied together and briefly held out together seeking better contracts.

In 1975, Kiick, Csonka and future Hall of Famer Paul Warfield left the Dolphins for the WFL. The package was a watershed worth nearly $4 million over three years for the three players, who played for the Memphis Southmen.

But the WFL folded, and Kiick returned to the NFL for his final two seasons, playing for Denver and Washington.

James Forrest Kiick was born Aug. 9, 1946 in Lincoln Park, New Jersey. He led Wyoming in rushing three years in a row and was inducted into their athletics Hall of Fame in 1996.

Miami drafted Kiick in the fifth round in 1968. He became a starter as a rookie and led the AFL in touchdowns rushing in 1969 with nine.

He had his best season statistically for Miami’s 1971 Super Bowl team, when he rushed for 738 yards and averaged 4.6 yards per carry, both career highs.

Kiick also was an excellent blocker and a threat as a receiver. He had 233 career receptions for 2,302 yards.

Following retirement, Kiick worked as a private investigator for the Broward County public defender’s office. His daughter, professional tennis player Allie Kiick, has been ranked in the top 150 on the women’s tour. His father, George, played fullback for the Pittsburgh Steelers in 1940 and 1945.