Loose forward Tom Christie scored two second-half tries for the Canterbury Crusaders as they relentlessly ground down the Otago Highlanders to record a 40-20 victory in their Super Rugby Aotearoa clash in Dunedin.

Winger Will Jordan also crossed once in each half as the Crusaders moved to the top of the table with their third victory in the competition, setting up a potential title decider with the unbeaten Auckland Blues next week in Christchurch.

It had looked ominous for the Highlanders as the Crusaders jumped out to an 8-0 lead through a Richie Mo'unga penalty and Jordan's try and were dominating the scrum.

Highlanders and All Blacks scrum-half Aaron Smith, however, began to direct his pack better and they stormed back with tries by Shannon Frizell and winger Ngane Punivai to take a 14-8 lead.

Two Mo'unga penalties dragged the Crusaders back into the game before Mitchell Hunt's penalty gave the home side a 17-14 advantage on the stroke of half-time.

Jordan continued to stamp his mark after halftime, his run setting up Christie's first try after the visitors dominated the opening 10 minutes of the second period.

The Highlanders effectively gave the Crusaders the only chance they needed to close out the game when replacement hooker Ash Dixon and winger Jona Nareki both failed to pass the ball to unmarked players less than 10 metres from the line.

Crusaders winger Sevu Reece gave them breathing room shortly afterwards before the visitors controlled possession to shift the momentum back in their favour.

Christie ensured victory three minutes from time with his second try before Jordan completed the scoring to complete his second successive two-try performance.