Toulon's Romain Taofifenua has been banned for three weeks after being found to have kicked Ulster's Stuart Olding in the head during Saturday's European Champions Cup match.
A disciplinary hearing in Dublin ruled that Taofifenua's offence had been "reckless and warranted a red card".
With the kick adjudged to be at the lower end of offences of this nature, a four-week ban was imposed.
The ban was cut by one week because of the player's conduct at the hearing.
Taofifenua, 24, will be free to play again on 17 November and both the player and the competition organisers have the right to appeal against the decision.
The Toulon second row was cited by the match citing commissioner Peter Larter [England] following the incident which happened in the 47th minute of the Pool 3 game at Kingspan Stadium.
Toulon's 23-13 victory allowed them to establish a four-point lead over nearest rivals Leicester Tigers and the Scarlets at the top of their group.
Ulster's hopes of progressing to the quarter-final stages of Europe's premier club competition appear remote as they have accumulated just one point from their opening two fixtures.