Scott Robertson watches over a Crusaders training session. Photo: John Davidson /

WELLINGTON, New Zealand - It will be mate against mate but no holds barred when the Canterbury Crusaders look to defend their unbeaten record against close rivals the Waikato Chiefs in Suva on Friday.

The pressure is mounting as the Super Rugby competition draws closer to determining the top eight, while New Zealand teams have the added weight of preparing for next month's British and Irish Lions tour.

The Crusaders and Chiefs, who have only lost one game, clash in a match which could determine both the outcome of the New Zealand conference and the overall top ranking.

The Chiefs, who have not lost to the Crusaders since 2014, have a reputation for provoking opponents, and Crusaders coach Scott Robertson has warned his players not to retaliate.

"There are a lot good mates and that adds to it," Robertson said. "There will definitely be a fine line with the intensity of it and the Chiefs like to live on that line.

"It is a really good point around our discipline and making sure that we execute and we are tough, without crossing that line."

In a clash with intriguing match-ups that will be closely watched by the All Blacks selectors, Crusaders skipper Sam Whitelock returns from a two-week suspension for striking an opponent, to face his Test locking partner Brodie Retallick.

In the midfield, All Blacks Ryan Crotty and Anton Lienart-Brown oppose each other with Crotty noting that the Chiefs "always bring physicality and niggle. You just expect that."

The fixture is a Chiefs home game but they have opted to swap the New Zealand winter for the Fiji warmth to acknowledge the contribution Pacific islanders make to New Zealand rugby.