Hooker Derick Kuun was the unlikely two-try hero as Bulls climbed to second on the Super 14 table with a 33-27 win over Chiefs on Saturday.

Chosen ahead of Springbok Chiliboy Ralepelle, Kuun crossed the line twice in the opening quarter of a Loftus Versfeld thriller and was voted man of the match.

His first try after a forward drive gave Bulls a lead they never surrendered and the second following a breakaway put the South Africans back in front against the resilient New Zealanders.

Centre Wynand Olivier grabbed the other Bulls try almost two minutes after the hooter sounded for half-time and fly-half Morne Steyn converted to give the Bulls a 27-20 advantage at the break.

Steyn was another pivotal figure for the Bulls, contributing 18 points from three penalties, three conversions and a drop goal to remain leading southern hemisphere championship points scorer with 116 this season.

Victory lifted Bulls to 33 points, one less than Hurricanes of New Zealand, and with two home fixtures to come followed by a visit to the Sharks, a top-two finish and a home semi-final is within reach.

"It was a pity we could not score a fourth try and claim a bonus point but I'll take the win. There was a lot of pressure out there and that is what the Super 14 is all about," said Bulls skipper and lock Victor Matfield.

Chiefs fullback and captain Mils Muliaina said: "Sometimes we are our own worst enemies. We lost some crucial line-outs on our throw and were not clinical enough on other occasions."

Among the self-inflicted wounds before a 35,000-plus crowd was the expulsion of number eight Sione Lauaki to the 'sin bin' nine minutes from half-time for a high tackle on Bulls wing Bryan Habana.

Chiefs centre Callum Bruce did break away for a try while his team were down to 14 men on a cool, autumn evening, but they also conceded a converted try and a penalty.

Lauaki and centre Richard Kahui were the other Chiefs try scorers while fly-half Stephen Donald, second highest point scorer behind Steyn, converted the three tries and kicked two penalties.

Bulls confront Western Force of Australia, who routed Lions of South Africa 55-14, next Saturday while Chiefs travel south to face Stormers in Cape Town.

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