Deion Sanders is the only person to play in both the Super Bowl and the World Series, not to mention the only player to ever hit a MLB home run and record an NFL interception in the same week.
On Oct. 11, 1992, he played in an NFL game and suited up for a MLB game … on the same day … in two different cities. That probably beats the time at Florida State when he won the 100 and 200 meters in a morning track meet and then started as a center fielder for the Seminoles' baseball team that night.