Waratahs coach Michael Cheika and referee Jaco Peyper have been reprimanded by Sanzar after chatting during the Tahs' win over the Blues.

Sanzar opened an investigation at the request of the Blues who were upset that Cheika had visited the referee's change room during the half-time break.

After undertaking an investigation, Sanzar found there had been a conversation between Cheika and Peyper in front of the other match officials over the interpretation at the scrums.

'In a short and polite exchange that took place in the referee's change room, Mr Peyper responded to Mr Cheika's request for clarification. No other issues were discussed. Both Mr Cheika and Mr Peyper have subsequently acknowledged this exchange should not have taken place and apologised,' Sanzar said in a statement.

'There is no evidence 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.

'Sanzar has issued formal warnings to both Mr Cheika and Mr Peyper and has written to all referees and coaches, reminding them that no discussions should take place between the match officials and coaches during a match.'

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