Kenyan runner Edwin Kipsang Rotichwas tackled by a member of the public while leading the pack on the final stages of the Kings Race, in Cuiabá, Brazil.
Rotich, who won the renowned Sao Silvestre Race in Sao Paulo, a little over a week ago, was immediately assisted by the local police.
Despite the incident, Rotich kept his lead and crossed the finish line in first place.
The attacker is 33-year-old Wallace de Sousa Nogueira who police said has a history of mental problems.
"He has a history of performing acts like these in the past, he's someone with (psychiatric) problems," said the local police officer, who arrested Nogueira after the incident.
Rotich was followed by his compatriot at the finish line, Mark Korir. Brazilian Daniel da Silva was third.