Toulon players Martin Castrogiovanni and Delon Armitage have received misconduct complaints for their behaviour during last Sunday's Champions Cup defeat by Leicester.
European Professional Club Rugby launched an investigation into the events at Welford Road and has decided the pair must face a three-man independent disciplinary committee in London on Wednesday.
Castrogiovanni sought out journalists after the match and directed an expletive-ridden tirade at Leicester director of rugby Richard Cockerill, who had claimed the former Italy prop swapped the Tigers for Toulon in 2013 for financial reasons.
Armitage, Toulon's English full-back who has a chequered disciplinary history, is alleged to have used offensive language at spectators at Welford Road.
"The misconduct complaint against Castrogiovanni is that he made a number of comments to the media in which he attacked, disparaged, criticised, damaged and/or brought into disrepute Cockerill, EPCR, the Champions Cup and the sport," an EPCR statement said.
"The misconduct complaint against Armitage is that during and after the match he is alleged to have conducted himself in an unsportsmanlike manner by making a number of comments to, or within earshot of, spectators using foul and abusive language and may have brought the sport into disrepute."