Colombia's Miguel Angel Lopez responded to a fan knocking him from his bike. (Alessandro Di Meo/ANSA/AP)

Colombian cyclist Miguel Angel Lopez was making a late uphill climb and hunting for a stage win on the penultimate day of the Giro d’Italia when a spectator who had been running alongside him collided with his bike and sent him to the ground.

Lopez responded with a firm slap to the man’s face.

In a video of the incident, Lopez can be seen getting up from the ground and swatting the man in the face. He then knocks the man’s cap off before returning to his bike.

According to the Associated Press, a collision with another spectator propelled the man, who was wearing a Slovenian flag on his back, into Lopez’s path. The cyclist would go on to finish in 18th place, 1:49 behind stage winner and teammate Pello Bilbao.

"I’m sorry for what happened; I was full of pure adrenaline,” Lopez said, according to ESPN. “But there needs to be more respect for the cyclists.”

The race jury voted to not penalize Lopez for the incident, calling it a “human reaction.” Union Cycliste Internationale rules state that an act of violence “toward any other person” should result in elimination from a race, but an exception was made in this case.

Lopez’s team manager, Giuseppe Martinelli, agreed with the decision.

“Some kind of punishment would be totally unfair after he was the one who was knocked down and lost time. If he’s punished, it’d be the end of cycling as a sport,” he told Cycling News.

Last year, a similar incident happened at the Tour de France when Italian cyclist Vincenzo Nibali collided with a fan and fractured his vertebrae.

The race’s final stage was Sunday, with Richard Carapaz becoming the first Ecuadoran rider to win the overall title.