The title race in Super Rugby will intensify in the sixth round as the ACT Brumbies and Chiefs meet in a top-of-the-table clash and teams leave the first third of the regular season behind.

The winner of Saturday's match in Canberra may end the round in first place and stake a claim to being title favorites, though that distinction is also in the sights of defending champion the Highlanders who host the Western Force in Dunedin.

The Stormers lead the South African group and share with the Highlanders the second rung on the overall ladder, though their threat to first place is made latent by their sixth round bye.

One team will probably emerge from the weekend matches as a clear front-runner as each of the leading teams have cleared some of the more testing phases of the season.

The Chiefs have won in South Africa, Argentina and New Zealand over the last three weeks and if they can win in Australia on Saturday, while still lacking as many as 12 frontline players through injury, they will have to be marked as title favorites.

Few teams from the Australasian group, which they lead by one point from the Highlanders and two points from the Brumbies, are likely to match the Chiefs' achievement of a clean sheet from matches in South Africa and Argentina.

For the Chiefs, the worst of the season is already over. From now on, they face away matches only against the Brumbies, New South Wales Waratahs and Queensland Reds in Australia and against fellow New Zealand teams.

The Brumbies have also put a South African tour behind them, losing their first match to the Stormers but winning their second against the Cheetahs to return to Canberra with a four-win, one-loss record.

They have matches remaining in New Zealand against the Highlanders and Auckland-based Blues but will otherwise see out the season with matches in Australia.

The Highlanders have won in Australia in each of the last two rounds, beating the Waratahs and the Rebels to extend their winning streak to four matches. They are likely to make it five consecutive wins on Friday when they meet the Force, who have been heavily beaten by the Hurricanes and Chief in their last two matches in New Zealand.

The Highlanders still have their South African and South American excursion to come: they will play the Kings in Port Elizabeth in round 15 and the Jaguares in Buenos Aires a week later before hosting the Chiefs in the final round of the regular season.

That draw seems extremely favorable: the Kings are the weakest of the South African teams and the Jaguares are likely to be worn down by travel and injuries by the late stages of the regular season.

The Stormers won in Buenos Aires last week, ticking an important box and cementing first place in the South African group, two points ahead of the Sharks who also have a bye this week.

They have still to play the Sunwolves in Tokyo, then face a late-season trip to Australia with winnable matches against the Melbourne Rebels and Force.

The Highlanders are likely to have beaten the Force and taken over first place on the overall tables by the time the Brumbies and Chiefs meet on Saturday. The Chiefs would take back first place with a win in Canberra against a Brumbies team taxed by the recent trip back from South Africa.

"The Chiefs are playing an amazing brand of rugby at the moment and hopefully we can keep up with that," Brumbies center Matt Toomua said. "It was nice to get away with the team (in South Africa) but now we're back at home in our comfort zone and ready to get stuck in."

Argentina's Jaguares are already beginning to show the effects of one of the tournament's most onerous travel schedules and have made nine changes for Saturday's match against the Blues in Auckland. Scrumhalf Martin Landajo will take over the captaincy from Agustin Creevy.

In another of the round's influential matches, the Johannesburg-based Lions, who are third behind the Stormers and Sharks in South Africa, host the Crusaders, who are nipping at the heels of the leaders in Australasia.

"We are right on our toes in preparation for this game," Crusaders assistant coach Brad Mooar told Fairfax Media. "They shape as potentially being the strongest South African team in the competition."

-AP