The Waratahs ended the Highlanders play off hopes with a 33-7 bonus point Super Rugby victory in Sydney.
The result moves the Waratahs into fifth place but leaves the Highlanders in 8th place on 45 points and with only one match remaining they cannot catch the rest of the field.
The Waratahs could however still miss out on the play offs as they face the resurgent Brumbies next week and the Highlanders could upset the Blues in Auckland on Friday.
The Waratahs got off to an early start with tries from Tom Carter and Dave Dennis before the Highlanders got on the scoreboard.
It took some time but the Highlanders got into their game and spent 10 minutes attacking the Waratahs in their 25 and eventually they got Jason Rutledge over for their first points.
Tony Brown added the conversion but the Waratahs hit back just before half time with another try by Tom Carter for a 19-7 half time lead.
The first points of the second half came in the final ten minutes when Tom Carter scored his third try which effectively sealed the match for the Waratahs.
The Waratahs were however not finished scoring as they added a fifth try in the final minutes.
Tom Carter's hat-trick of tries keeps the Waratahs in the hunt for a Super 15 Rugby play-off spot but they will still need to beat the Brumbies next weekend. .
The Waratahs scored five tries with Wallaby fullback Kurtley Beale in irresistible form to end the Highlanders' outside play-off hopes with just one round left to the top-six play-offs in the southern hemisphere championship.
Beale set up Carter's opening try and finished the night by also laying on his side's fifth try for replacement back Josh Holmes, kicking across field for Holmes to storm on to the ball and race away to score.
Beale landed four conversions to round off an influential night for the injury battered Waratahs.
The Sydneysiders paid a price for their win with Wallaby back Berrick Barnes again failing to complete a game.
He was replaced after 33 minutes while Wycliff Palu came off with a shoulder injury in the second half.
Skipper Phil Waugh, who played 40 minutes in his comeback match from a hamstring injury, said he was proud of his team's performance.
"We got stuck there a little bit after halftime but the guys have just got back from South Africa and to come out the way we did and get that bonus point is going to be pretty important, " Waugh said.
"The Highlanders are a tough team to play and the guys hung in well and it's really pleasing to return to Sydney and perform the way we did. "
The Waratahs climbed back into the top six but their stay is dependent on other results in South Africa this weekend.
Beale, who is heading to the Melbourne Rebels next season, was in terrific form and was the difference as the Waratahs swept to a 12-0 lead inside the opening 15 minutes.
He slipped two tackles and then grubber kicked for Carter to score in the corner and six minutes later he counter-attacked from deep inside his own half and grubbered again in the leadup to Dave Dennis scoring.
Otago scored their only points through a converted try by Jason Rutledge before Carter crashed over for his second try to give the Waratahs a 19-7 halftime lead.
The Waratahs were marooned for much of the rain-lashed second half before finishing the stronger with Carter clinching his hat-trick and Holmes scoring.
It was the Highlanders' third straight loss and ended their faint play-off hopes.
"We had a lot of field position and we played tight in the middle and turned over some ball at critical times and when you can't score points you can't build pressure, " said Highlanders skipper Jamie Mackintosh.
The Waratahs finish their regular season at home to the Brumbies next week, with the Highlanders away to the Blues.
Final Score Waratahs 33 Highlanders 7
Tries - T Carter 3, D Dennis, J Holmes
Con - K Beale 4
Tries - J Rutledge
Con - T Brown
Referee: Chris Pollock
Assistant referees: James Leckie, Andrew Lees
Television match official: Matt Goddard
Waratahs : 15. Kurtley Beale , 14. Lachie Turner , 13. Tom Carter , 12. Berrick Barnes , 11. Sosene Anesi , 10. Daniel Halangahu , 9. Luke Burgess , 8. Wycliff Palu , 7. Phil Waugh [c] , 6. Dave Dennis , 5. Sitaleki Timani , 4. Dean Mumm , 3. Al Baxter , 2. Tatafu Polota-Nau , 1. Benn Robinson
Reserves , 16. John Ulugia , 17. Jeremy Tilse , 18. Pat O'Connor , 19. Chris Alcock , 20. Hugh Perrett , 21. Josh Holmes , 22. Atieli Pakalani.
Highlanders:1. Jamie Mackintosh (C) , 2. Jason Rutledge , 3. Bronson Murray , 4.Jarrad Hoeata , 5.Josh Bekhuis , 6. Adam Thomson , 7. Alando Soakai , 8. Nasi Manu , 9. Aaron Smith , 10.Tony Brown , 11. Siale Piutau , 12.Shaun Treeby , 13. Kendrick Lynn , 14. Kade Poki , 15. Ben Smith
Replacements: 16. Mo Schwalger , 17. Chris King , 18. Nick Crosswell , 19. John Hardie , 20. Jimmy Cowan , 21. Robbie Robinson , 22. Telusa Veainu