While serving as referee of the 1999 NFC Championship game between Tampa Bay and St. Louis, Carollo overturned a catch by Tampa Bay's Bert Emanuel, that later led to the adoption of the Bert Emanuel Rule. The play consisted of Bert Emanuel making what was ruled a catch at St. Louis' 22-yard line with 47 seconds left in the game and the Buccaneers down by 5. After review, Carollo ruled that the tip of the ball had touched the ground, and even though Emanuel maintained control of the football, Carollo had to rule it an incomplete pass. This led to the NFL clarifying the definitions of both a catch and an incomplete pass, as to avoid this scenario replaying itself in the future. This is known as the Bert Emanuel Rule.