Waratahs top but play-off picture still fuzzy

New South Wales Waratahs looked every inch champions-elect as they locked up top spot in the Super Rugby standings on Sunday, but the play-off picture beneath them was not much clearer after the penultimate week of the regular season.

Fullback Israel Folau's 12th try of the campaign helped the Waratahs to a dominant 44-16 victory over the Otago Highlanders that gave them an unassailable 53 points and guaranteed them home advantage for the semi-finals, and potentially the final.

The Waratahs and South Africa's Sharks were already assured of topping their national conferences before the weekend and the Canterbury Crusaders were the only other team to join them in the postseason.

The Crusaders top the New Zealand standings with 46 points after Dan Carter, returning from his sabbatical, helped them to a 21-13 victory over the Auckland Blues on Saturday that earned them play-off rugby for the 13th straight season.

That leaves three places still up for grabs in the final weekend of the regular season, which is followed by the four-team wildcard play-offs.

The Highlanders, who have 42 points, could still overtake the Crusaders and win the New Zealand conference if they can prevail in a South Island showdown with the seven-times champions in Christchurch this weekend.