Clermont wing Naipolioni Nalaga has been cleared to play for his club in their European Cup Round Two match against Harlequins at Stade Marcel-Michelin on Sunday.
Although the citing complaint against Nalaga, arising from the European Cup Round One match against Racing Metro last Sunday, was upheld, he is still free to play.
Nalaga appeared at a disciplinary hearing in Dublin on Thursday.
However, it was also decided that the yellow card shown to the player during the match by referee Nigel Owens (Wales) was a sufficient sanction.
As a result Nalaga is free to play on Sunday.
Nalaga was alleged to have struck the Racing Metro wing Marc Andreu with his knee during the second half of the match at Stade Yves du Manoir - in contravention of Law 10.4(a).
The complaint was made by Irish citing commissioner John West.
Under ERC's discipline rules, the complaint was referred by ERC disciplinary officer Roger O'Connor to a 'gatekeeper' for review.
The gatekeeper, Douglas Hunter of Scotland, considered the evidence and found that in his opinion the incident warranted a red card and that the citing should proceed.
Law 10.4(a) Punching or striking. A player must not strike an opponent with the fist or arm, including the elbow, shoulder, head or knee(s)
However, judicial officer Antony Davies (England) decided that the yellow card was a sufficient sanction.