Leicester Tigers director of rugby Richard Cockerill has described Martin Castrogiovanni's verbal attack on him as "petulant".
The former Tigers prop launched a lengthy tirade at Cockerill following Toulon's defeat to Leicester on Sunday.
The Italy international was angered by claims that he left Leicester for Toulon in 2013 over money, but Cockerill believes that the 33-year-old's outburst was unnecessary.
"He has no understanding of what it takes to run a rugby club," Cockerill told BBC Sport. "It is not for him to comment.
"We have some very big-hitters on the board. To call them amateurs and to use the language that was used against the club and myself was inappropriate to say the very least, and untrue. We're the most successful English club of all time. It's a petulant outburst that will no doubt get him in hot water."
Toulon have apologised to Leicester for Castrogiovanni's words and have promised to investigate the incident.
