Sean O'Brien punch on Pascal Pape likely to result in citing - but was it an act of revenge for Jamie Heaslip knee incident?

Heaslip suffered three broken vertebrae during the Six Nations when Pape struck him in the back withj his knee during the Six Nations

Ireland flanker Sean O'Brien could face disciplinary action for a punch on Pascal Pape (Getty Images)

Sean O’Brien was one of the key reasons why Ireland ran out 24-9 winners over France in the shootout to top Pool D, but the man of the match performance may have been his last at the 2015 Rugby World Cup.

O’Brien was picked up early in the match punching France lock Pascal Pape in the stomach as the pair stood on the fringe of a ruck. Pape required prolonged treatment after the blow – which left him in a heap on the floor – while the incident went unnoticed by both referee Nigel Owens and the Television Match Official Graham Hughes.

O’Brien is almost certain to be cited for the incident, and depending on whether he is found guilty and banned or not, he could miss the rest of the tournament with a three week ban enough to end his participation at the World Cup regardless of how far Ireland go.

Pape was able to continue after treatment, although the French were down to 14 men for a few minutes while he was tended to by medics, and he was eventually replaced by Alexandre Flanquart when the game was beyond France which leaves them facing the daunting prospect of tackling New Zealand in the quarter-finals.

Watch the video below…

However, was O’Brien’s punch a premeditated act?

Barely a minute had gone by when O’Brien took aim at the second-row, and despite Pape appearing to have a hand on O’Brien, he may have lashed out in an act of revenge for his Leinster back-row colleague Jamie Heaslip.

The No 8 fell victim to Pape in the Six Nations when the Frenchman was yellow carded for kneeing Heaslip in the back. The incident left Heaslip with three broken vertebrae, and Pape was subsequently banned for 15 weeks, which was reduced to 10 weeks after Pape made a public apology which was accepted with grace by the Irishman.

Watch the incident from the Six Nations below…

It remains to be seen if and when World Rugby take action against O’Brien, who is likely to have broken Law 10.4 (a) of the World Rugby regulations as Pape did which forbids a player from punching or striking an opponent.

Pascal Pape receives treatment after being punched by Sean O'Brien (Getty Images)

Any suspension could have huge ramifications for Ireland head coach Joe Schmidt. The New Zealander will today discover the full cost of the win over France with injury updates on captain Paul O’Connell, Jonathan Sexton and Peter O’Mahony.

Watch full match highlights from Ireland’s win over France below…

O’Connell’s injury looks almost certain to end his World Cup after the lock left the field in agony on a stretcher. O’Mahony was also carted off the field although Schmidt did reveal that he was able to walk under his own weight, while there was slightly better news in regards to Sexton who was personally confident of facing Argentina despite leaving the field with a damaged groin and tender ribs following a strong tackle from French No 8 Louis Picamoles.

Bot Keith Earls and Cian Healy also left the field with knocks, and with a quarter-final against Argentina at the weekend, Schmidt will need to decide quickly if injury replacements are need to be brought into his squad.