The out-half's actions were missed by the match officials but will almost certainly be picked up by the citing commissioner, Italian Alberto Recaldini, who has 50 hours from the start of the match to indicate whether a citing is imminent.
The incident – which was highlighted by video stills (right) – also led to a confrontation between the two players before O'Gara was hastily replaced by Ian Keatley. If Recaldini deems the incident to have been an act of foul play, then O'Gara will be called to a disciplinary hearing later this week.
O'Gara's excellent disciplinary record – he has never been red-carded in the Heineken Cup – will stand in his favour should he be cited, but fears were growing among the Munster faithful last night that he may face a suspension.
Were he to be found guilty and banned, it would be an enormous blow to Munster's hopes of securing the bonus-point win they need from their pool finale in Thomond Park.
If he is suspended for the game then Keatley will start, with JJ Hanrahan – who kicked two penalties and a conversion in the Munster 'A' side's B & I Cup win yesterday – on the bench.
Munster's win over Edinburgh keeps them in the hunt for the final quarter-final slot.
They are level with Leinster on 15 points but have scored one more (nine) try than the defending champions.
It is increasingly likely that Montpellier, who finished Round Five as the best-placed of the six teams positioned second in their pools on 18 points, will qualify as they host compatriots Toulon – who are already qualified – with Leinster and Munster battling it for that final qualification place.