Pinto was shown a yellow card, later upgraded to red, for the incident late in the Pool C match and his argument that it failed to meet the threshold for dismissal fell on fallow ground at a judicial hearing on Tuesday.
The French-born Pinto will miss Saturday's clash with Georgia in Toulouse and Portugal's third pool game against Australia but will be able to play against Fiji on October 8th if he undergoes a World Rugby coaching intervention programme.
There was better news on Tuesday for his teammate Rafael Simoes (32), who was cleared to play against Georgia after a disciplinary hearing cleared him of a dangerous tackle.
The number eight was cited after the 28-8 loss to Wales but, while admitting that he had committed a foul, successfully submitted that it did not meet the red-card threshold.
Portugal coach Patrice Lagisquet will name his team for the Georgia match on Thursday.