The Canterbury Crusaders went to the top of rugbys Super 12 table with a less than convincing 22-13 defeat of the New South Wales Waratahs who saw their semi-final dreams buried on Lancaster Park here Friday night.

The Waratahs led 13-10 at half-time as the Crusaders discovered the less than delightful pleasures of life without their ace kicker, flyhalf Andrew Mehrtens who is nursing rib injuries.

The game lived up to the reputation the Super 12 now has as the world's toughest rugby competition but in the wintry conditions it was dominated by turn-over ball, fumbling and at times very pedantic refereeing from South African Tappe Henning.

He had the whistle at last weeks now celebrated game where the Waratahs managed to lose 25-30 despite their rivals, the Wellington Hurricanes, being down to 13 men.

Only toward the end of Fridays game did the Australians look as inept this time.

First points went to the Waratahs off Matt Burkes boot.

Eight minutes into the game the Crusaders mounted a series of backline assaults, looking for weakness in what had been a weak defence last week.

The Waratahs had hardened up but Leon MacDonald managed to infiltrate and go over. But it was a close call and needed the video referee to decide on whether he actually scored.

The Crusader defence looked good for much of the early game until suddenly Christian Warner, in what seemed an easy movement and good speed, flashed in for a Waratah try at the 15 minute mark.

Burke converted and later pushed them further ahead with a penalty.

The Crusaders forwards were engaged in a series of rugged rucks and mauls 26 minutes into the game but their backs could never quite make it through a steady Waratah backline until half-back Justin Marshall jinxed in for a try.

Again it was unconverted, the absence of Mehrtens noted.

The second half began with a long period of play dominated by seemingly routine turnovers by both sides. The quality of play flagged markedly as Crusaders kept letting the Waratahs into the game.

A midfield Canterbury scrum saw the ball out to Scott Robertson -- a strong Canterbury star -- who was able to set up some good second phase ball that push the big Fijian winger Marika Vunibaka over for in the 53rd minute.

The Crusaders have already got a semi-finals berth and it showed; the Waratahs had a slim hope for one and they fought hard for it. Heartbreak came at the 70 minute mark.

The Waratahs had set up a marvellous attacking lineout, right on the Crusaders line. But they fluffed it and the ball went into far and was swept in by Crusader Mark Robinson who bolted up field before off-loading to Vunibaka who completed the rest of the run, with some fends and a good deal of speed, to score a try.

The humiliation was completed when the Waratahs were awarded two successive five metre scrums. And on both occasions the Crusaders simply pushed them right over the ball.