Toulon pair Martin Castrogiovanni and Delon Armitage will face misconduct charges after incidents at the European Rugby Champions Cup match at Leicester.
Castrogiovanni, 33, is alleged to have made unacceptable comments to the media about Leicester and the club's director of rugby Richard Cockerill.
Former England full-back Armitage, 30, is alleged to have used offensive words in front of fans.
The cases will be heard by an independent Disciplinary Committee.
Former Leicester prop Castrogiovanni has been left out of the return fixture in France on Saturday but Armitage has been named on the wing.
European Professional Club Rugby (EPCR) said in a statement: "The misconduct complaint against Martin Castrogiovanni is that after the match he made a number of comments to the media in which he attacked, disparaged, criticised, damaged and/or brought into disrepute Leicester Tigers, the club's Director of Rugby, Richard Cockerill, EPCR, the European Rugby Champions Cup and the sport of rugby union."
It added: "The misconduct complaint against Delon 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."