NSW Waratahs defence coach Nathan Grey denies his side has a discipline problem, despite evidence to the contrary in the opening two rounds of the season.

Tolu Latu was supended for one week in round one for punching Matt Toomua, while forwards Dean Mumm and Will Skelton were both sin-binned against the Brumbies last weekend.

The Waratahs have conceded more penalties than any other team so far this Super Rugby season and have had three players yellow carded in the opening two rounds.

“In terms of discipline, it's not an issue for our side at all,” Grey said.

“It's just a matter of making sure that we're making the right decisions at the right time.

“Trusting what we're doing to be able to put pressure on the opposition with our defence and also our attack.

“Not feeling as though they have to force the issue at the breakdown and getting off-side, or taking the law into their own hands.”

The Waratahs have a bye this week, before facing the Highlanders at Allianz Stadium in round four.