The Waratahs won their fourth straight Super Rugby match with a 33-17 victory over slumping defending champions, Waikato Chiefs.
The Australians remain in the hunt to win their conference but the Kiwis - who led midway through the second half - are now facing the very real prospect of missing out on a wild card spot.
Aaron Cruden kicked the hosts into an early lead in New Plymouth with a penalty, but Bernard Foley replied.
New South Wales star Alofa Alofa had a try disallowed by the TMO but the visitors did not have to wait much longer for their first try.
Israel Folau went over after some excellent work from Australia team-mate Adam Ashley-Cooper, Foley booting the conversion.
Foley extended the lead with a penalty on the half-hour mark as the Waratahs turned around 13-3 up.
The Chiefs came out for the second-half pumped up and cut the gap on 50 when Bundee Aki pounced on a clever Cruden chip to touch down and the fly-half added the extras.
The Waratahs added another three points with a Kurtley Beale penalty but the Chiefs then went in front when Aki was first to Tom Marshall's grubber, and when Cruden converted the hosts were suddenly 17-16 in front.
But the wheels then came off. From there on in it was all Waratahs with Foley booting a penalty before skipper Dave Dennis rampaged over down the blindside and Foley added the extras.
Foley then added another seven points as he converted his own score in the final minute to seal the win.
Dennis said: "We were really keen to put in a strong performance and are really pleased with the result. We kept playing, kept attacking with the ball in hand and got some good tries in the end."