The Waratahs scored four tries and survived a set-piece mauling to secure a seventh straight victory this season and their biggest win over a shambolic Reds side at Suncorp Stadium on Saturday night.

With top spot on the ladder already in the bag, Kurtley Beale scored a double for the minor premiers and sliced and diced the Queensland defence to put the side to a 27-3 lead by the 55th minute.

In an ominous sign of things to come when the Waratahs host a home semi final at Allianz Stadium in a fortnight against what will presumably be a much more dangerous opposition, the Reds had NSW on a platter at the set piece, winning five lineouts against the throw in the first half but hobbling themselves with an embarrassment of turnovers and handling errors.

In a horror closing stand to end a nightmare season, the 2011 champions could summon neither the will nor skill to score despite ample opportunities, allowing the Waratahs to score all but three of the 37 points on offer in a spiteful but plodding interstate derby.

Queensland lost five-eighth Ben Lucas with a knee injury in the eighth minute and centre Ben Tapuai to concussion in the 17th, leaving a back line on the field without a single first-choice starter.

But there was no excuse for the litany of basic skill errors and soft moments in defence from the cowed former champions. NSW were strong in attack but were vulnerable during a 15-minute period of intense try line pressure in the first half, not least when prop Sekope Kepu was sin-binned for foul play.

And yet Queensland could not score. NSW go into a week off before their first semi-finals appearance in four years and the Reds go into what must surely be the most ugly of season review sessions in the club's recent history.

Harris opened the scoring with a penalty goal in the fourth minute and Foley missed two opportunities to answer in the next four minutes.

Lucas limped off in the eighth minute and the Waratahs built pressure. Beale tormented the Reds' defensive line, having his way on every occasion before setting up fullback Jono Lance's try in the 13th minute.

Foley converted to put the Waratahs in front 7-3 but Beale wasn't finished.

The Waratahs exploited an overlap on the right wing and Cam Crawford showed a glimpse of his 2013 form to give Beale acres of space for a 30m dash to the line.

Foley converted to make it 14-3 with 17 minutes gone while play was suspended to see Reds centre Ben Tapuai stretchered off after going down in contact with Crawford.

Replacement back JJ Taulagi shot Rod "Rocket" Davies a flick pass but the Queensland winger lost it on the line under desperate defence from NSW captain Michael Hooper.

The home side kept the pressure on, hoping to convert their set piece ascendancy to points.

But despite a worryingly shaky line out the Waratahs defence - solid all season - did the job again at Suncorp, comfortably shutting the Reds out for a spiteful 15 minutes of classic derby nastiness.

Kepu, cool as a cucumber for most of the season, was caught pulling Reds flanker Beau Robinson's hair at a ruck and appeared to unleash two quick upper cuts in the ensuing fracas.

He was sent to the sin bin in the 28th minute, leaving Queensland one man up and within spitting distance of the try line, but they could not convert.

The Waratahs were up 17-3 at half time and piled on two more tries to Beale and halfback Nick Phipps to secure a 34-3 win before a week off heading into a home semi-final.