HAMILTON, NEW ZEALAND - MAY 25: Tawerau Kerr-Barlow of the Chiefs passes during the round 14 Super Rugby match between the Chiefs and the Bulls at Waikato Stadium on May 25, 2012 in Hamilton, New Zealand. (Photo by Phil Walter/Getty Images)

Sydney – New Zealand's Waikato Chiefs took the outright Super 15 lead with a win over the Northern Bulls in this weekend's 14th round as their other South African rivals the Western Stormers also faltered.

The Chiefs pulled three points clear at the top of the standings with four matches to go until July's top-six playoffs after a hard-fought 28-22 defeat of the Bulls in Hamilton.

The Chiefs, who never won the southern hemisphere provincial championship and lost to the Bulls in the 2009 final, finished strongly to beat the three-time champions three tries to one.

The Stormers, who went into this weekend's round leading on points difference, went down 25-20 to the Coastal Sharks in an all-South African match in Durban.

The ACT Brumbies had their lead in the Australian Conference reduced to five points after losing 13-12 at home to defending champions Queensland Reds.

Seven-time champions Canterbury Crusaders are in fifth spot after their weekend bye, ahead of the Sharks.

New Zealand contenders Otago Highlanders and Wellington Hurricanes kept in the hunt for the playoffs.

The Highlanders broke a 10-year jinx as they held off the strong-finishing Auckland Blues 27-20 at Eden Park, while the Hurricanes totted up nine tries in a 66-24 demolition of the Melbourne Rebels in Wellington.

In the weekend's other games, Central Cheetahs held on in a tense finish to pip the New South Wales Waratahs 35-34 in Bloemfontein, while Australia's coach-less Western Force prevailed in the battle of the Super 15 cellar-dwellers, beating South Africa's Golden Lions 17-11 in Perth.

The lead changed six times in Hamilton before the Chiefs secured victory with a Sam Cane try 10 minutes from time.

The Pretoria-based Bulls led 20-6 early in the second half, but the Chiefs lifted and claimed a significant win when Cane latched onto a Sonny Bill Williams offload for the Chiefs' third try.

The Sharks played themselves back into title contention with their fourth successive win to down the Stormers at Kings Park.

The Stormers had won 10 of their first 11 matches, but were knocked out of their stride by a combative Sharks team, who dominated the scrums and were stronger at the breakdown.

Queensland Reds had to survive a last-gasp penalty attempt from Brumbies flyhalf Zack Holmes before prevailing in Canberra by a point.

Fullback Luke Morahan scored the only try of an attritional Australian derby in the third minute with the remainder of the drab match decided by goalkicking.

The Highlanders secured only their second victory against the Blues in Auckland in 17 years of Super rugby.

The Blues, who languish near the bottom of the table, left several All Blacks on the bench and fell behind 27-6 to the Highlanders with 20 minutes to go.

But the mood changed when Ali Williams, making his 100th Super appearance, Daniel Braid, Piri Weepu and Ma'a Nonu were introduced to the game and the Blues were rewarded with two late converted tries give them a chance to draw the match.

The Hurricanes posted a record Super rugby score against the Rebels with Julian Savea scoring three tries while Andre Taylor and Alapati Leiua added two each. Beauden Barrett converted all nine tries and added a penalty for 21 points.

The Hurricanes now sit just outside the cut-off point for the play-offs in a cluster involving the Sharks, Highlanders and Reds in a battle for sixth place. – Sapa-AFP