Sharks coach John Plumtree raised the stakes ahead of his team's crunch encounter with Super Rugby pace-setters the Brumbies on Saturday.

Plumtree decided to highlight aspects of the Brumbies' scrum tactics he felt may be suspect and suggested referee Jonathan Kaplan could play a role in stamping out any illegal play.

In two packs littered with internationals, the contest at the set pieces are always going to be searing.

However, Plumtree feels that at scrum time the contest may be even more trying because of the opposition's tactics.

The Sharks will start with an all-Springbok front row of Jannie du Plessis, Craig Burden and Tendai Mtawarira.

The Brumbies have two Wallabies - veterans Ben Alexander and Stephen Moore - as well as a rookie, Scott Sio, at the front end of their scrum.

"We're pleased to have Jonathan Kaplan refereeing this match," Plumtree said in an interview on the Sharks website.

"There are some things we've spotted with the Brumbies scrum that we aren't happy with and they have been penalised for that," the Sharks mentor added.

"We're hoping he [Kaplan] looks after those areas designed to de-power our scrum, we're hoping they don't get away with that this weekend."

Plumtree was full of praise for the South African referee, hinting that the match official may well play a crucial role in the game.

"We know what to expect from him [Kaplan], we've had him many times," the coach said.

"He's a very strong ref and that's what we want.

"The breakdown, is an area the Brumbies have conceded lots of penalties in the last couple of games, so we need to be very accurate and hopefully he will be really strict on the breakdown and scrummaging."