Robert Lee Hayes (December 20, 1942 – September 18, 2002), nicknamed "Bullet Bob", was an American sprinter and professional football player. After winning gold medals at the 1964 Summer Olympics, he played as a split end in the National Football League (NFL) for the Dallas Cowboys (for 11 seasons). Hayes is the only athlete to win both an Olympic gold medal and a Super Bowl ring. He was a two-sport stand-out in college in both track and field and football at Florida A&M University. 

Hayes was enshrined in the Dallas Cowboys Ring of Honor in 2001 and was selected for induction in the Pro Football Hall of Fame in January 2009. Hayes is the second Olympic gold medalist to be inducted to the Pro Football Hall of Fame, after Jim Thorpe. He once held the world record for the 70-yard dash (with a time of 6.9 seconds). He also is tied for the world's second-fastest time in the 60-yard dash. He was once considered the "world's fastest human" by virtue of his multiple world records in the 60-yard, 100-yard, 220-yard, and Olympic 100-meter dashes. He was inducted into the United States Olympic Hall of Fame.

At the 1964 Summer Olympics, in Tokyo, Hayes had his finest hour as a sprinter. First, he won the 100m and in doing so tied the then world record in the 100 m with a time of 10.06 seconds, even though he was running in lane 1 which had, the day before, been used for the 20 km racewalk and this badly chewed up the cinder track. He also was running in borrowed spikes because one of his shoes had been kicked under the bed when he was playing with some friends and he didn't realize until he got there. This was followed by a second gold medal in the 4×100 meter relay, which also produced a new World Record (39.06 seconds)

Hayes' first two seasons were most successful, during which he led the NFL both times in receiving touchdowns with 12 and 13 touchdowns, respectively.[11] In 1966 Hayes caught six passes for 195 yards against the New York Giants at the Cotton Bowl. Later, in the Dallas Cowboys-Washington Redskins match-up, Hayes caught nine passes for 246 yards (a franchise record until Miles Austin broke it with a 250-yard performance on October 11, 2009, against the Kansas City Chiefs). 

Hayes' speed forced other teams to go to a zone since no single player could keep up with him. Spreading the defense out in hopes of containing Hayes allowed the Cowboys' talented running game to flourish, rushers Don Perkins, Calvin Hill, Walt Garrison and Duane Thomas taking advantage of the diminished coverage at the line of scrimmage. In the 1967 season, Hayes led the NFL in punt return yards, and went on to set an NFL playoff record with 141 punt return yards in Dallas' 52-14 win over the Cleveland Browns. Hayes also caught 5 passes for 145 yards in that game, including an 86-yard touchdown catch.