New South Wales Waratahs coach Michael Cheika and referee Jaco Peyper have been reprimanded by Super Rugby's governing body SANZAR.
The pair had a discussion at half-time during the Sydney side's recent home win over the Blues, which isn't allowed under SANZAR rules.
The Blues reportedly filed a complaint about Cheika visiting the match officials' changing rooms at the break, and SANZAR says after an investigation they're satisfied it was just to clarify an interpretation of refereeing the scrums.
"Both Mr. Cheika and Mr. Peyper have subsequently acknowledged this exchange should not have taken place and apologised," SANZAR said in a statement.
The New Zealand Herald newspaper reported there had been suggestions from the Blues they had noticed a "massive difference in interpretation and application of the laws they encountered in the second half."
SANZAR, though, said Cheika's discussion did not affect the match.
"There is no evidence that the referee was influenced by the exchange in his handling of the match, nor in the circumstances has there been a breach of the SANZAR Code of Conduct and no further action will be taken," the statement added.
It's not the first time that Cheika, who steps down from the Waratahs at the conclusion of the tournament to focus solely on the Wallabies, has fallen foul of rugby officialdom.
Cheika's actually a serial offender in relation to referee dust-ups.
Last year he was given a suspended six-month ban and fined for abusing a cameraman in South Africa. The ban, suspended until the end of August, would be activated if he breached the code of conduct again.
Cheika, who was also warned by SANZAR in 2013 and smashed a glass door in a coaches box in Canberra the following year in a fit of pique, was also fined after abusing match officials during and after Stade Francais' loss to Harlequins in the 2011 final of a European competition.