The French rugby federation has been reprimanded for failing to follow head injury assessment (HIA) protocols during the conclusion to March's Six Nations win over Wales in Paris.
Wales' interim head coach Rob Howley said the "integrity of the game had been brought into disrepute" after France replacement prop Uini Atonio went off for a head injury assessment, with starting tighthead Rabah Slimani then returning.
But an untoward incident review group (UIRG) appointed to investigate the incident concluded "there was no clear evidence that there was any intent to obtain a competitive advantage".
Slimani had earlier been replaced, but the France team doctor insisted that Atonio needed an HIA, therefore allowing Slimani to go back on as Les Bleus laid siege to Wales' line through a series of scrums.
Wales' view was the HIA process had apparently been used as a method of getting superior scrummager Slimani back on as France looked to exert set-piece dominance in pursuit of a winning try, which duly happened in the 20th minute of stoppage time of the home side's 20-18 win on March 18.
Howley claimed that a member of France's coaching team ran outside the designated technical area, which is not allowed, and spoke to Les Bleus' team doctor, who then went on to the pitch and told referee Wayne Barnes that Atonio needed an HIA.
Just before that, following the doctor's first pitch arrival, Barnes asked Atonio if he was injured, and the player said he had a sore back but could play on.
Wales conceded a try and 100th-minute conversion as France triumphed to secure a third-place finish in the championship, while Wales ended up fifth.
Match day video footage was scoured and interviews were taken and Six Nations Rugby said that following a detailed review of the available evidence it was determined that, once HIA protocols had been initiated, "the FFR conducted the process appropriately although there was some miscommunication from the French team".
However, Six Nations Rugby also said that there had been failings by the FFR over its application of HIA protocols and the governing body has issued a letter of reprimand.
A statement read: "The UIRG concluded that the FFR had not complied with HIA protocol and/or the relevant laws of the game, and to this effect a letter of reprimand has been issued by Six Nations Rugby.
"There was no clear evidence that there was any intent to obtain a competitive advantage in the match with regards to the FFR's failures in complying with the HIA protocol and/or laws of the game."