Horan, wearing an unusual multicoloured costume, ran from the pavement to De Lima’s left and grabbed the Brazilian, pushing him into the crowd on the right.

The IAAF swiftly confirmed that the marathon result would stand, despite De Lima having been leading at the time of the incident and eventually finishing third.

But the IOC, recognising the injustice to De Lima, have decided to present the Brazilian with their coveted Pierre de Coubertin medal.

An IOC spokeswoman said: “We have decided to do this in recognition of de Lima’s exceptional demonstration of fair play and Olympic values during this evening’s marathon.”

De Lima was due to receive his special award during the medal ceremony when he was to be presented with his bronze medal for finishing third.

The attack comes after an almost unblemished Games in terms of security.

And while the International Association of Athletics Federations also offered their sympathy to De Lima, they confirmed that the result of the race would be unaltered.

“The race jury has reviewed a video of the race,” the IAAF said in a statement.

“We would like to express our sympathy towards the athlete and regret the unfortunate incident.

“This shall not happen in the future and the security should be reinforced for road events.

“The IAAF is asking the Greek authorities to identify the responsible person and take the appropriate sanctions.

“The final result can unfortunately not be changed.”

The face of the marathon tonight was already changing before the intrusion, with De Lima’s lead being gobbled up quickly.

Soon after the incident, he was passed and had to settle for the bronze.

Taking the gold medal was Italian Stefano Baldini, while the silver medallist was American Mebrahtom Keflezighi.

De Lima finished in front of Briton Jon Brown, who finished fourth, just as he had done in Sydney four years ago.

World record holder Paul Tergat of Kenya was in the pack which contained Brown, as were Ethiopian Ambesse Tolosa, Moroccan Jaouad Gharib, American Mebrahtom Keflezighi and Italian Stefano Baldini. Kenyan Eric Wainaina, a silver medallist in Sydney, was also up in contention.

De Lima had apparently gone out too quickly, and too soon, and regardless of the attack it was hard to see him maintaining his lead.

Baldini completed the course aggressively, clocking 2:10:55, while Keflezighi came home in 2:11:29, ahead of Lima who struggled on his lap of the Panathinaiko Stadium, finishing in 2:12:11.

Brown, missing out on a medal again, was officially timed at 2:12:26.