Melbourne Rebels coach Tony McGahan conceded his depleted troops were powerless to stop superstar trio Israel Folau, Bernard Foley and Michael Hooper as the NSW Waratahs kept their Super Rugby finals hopes alive with a 50-point clinic on Sunday.

The Waratahs overcame a shambolic start to annihilate the Rebels 50-23, with the Wallabies big guns headlining the 2014 champions' first home win since round one.

Folau bagged a tryscoring double, Foley also delivered an attacking masterclass, while Hooper's inspirational 80-minute performance earned the skipper man-of-the-match honours at Allianz Stadium.

In contrast, after an encouraging opening quarter, the injury-ravaged Rebels were unable to contain the rampant Tahs after losing Wallabies centre Reece Hodge in the second minute and needing to turn to their 38th different player this season by fulltime.

"The end tale of the game was that we tried manfully with the troops that we had," McGahan said.

"Losing Reece early on doesn't help us and we've got a few guys coming on after a long time out of the game and they take time to gel.

"But I thought we competed as hard as we could. Hooper, Israel and Foley were absolutely outstanding.

"When you've got three key players and they have such influence, not only in the game itself but also on their other teammates about what they can do, I thought they were fantastic.

"They brought the rest of the group through with a lot of key moments there."

Waratahs coach Daryl Gibson hailed the eight-tries-to-three drubbing as the perfect platform for a challenging two-game block in New Zealand against the Highlanders and Chiefs.

"We know the road ahead of us is a tough one, but certainly that's an excellent start," Gibson said.

"It's what we trained all week. We stripped our game right back to quite a basic game and off the back of that, good things started to happen.

"We wanted to make sure that we got the full five points out of this team because we know that's what we need to do, and we did, and that's pleasing.

"Scoring 50 points, that's really positive. That's a blueprint for us."

But banking any points looked in great doubt early after the competition's worst starters took their first-half struggles to new levels.

An exasperated Hooper confessed to being unable to control his ill-disciplined Waratahs after the home side conceded the first seven penalties of the match.

Referee Angus Gardner was forced to pull out his yellow card as hooker Tolu Latu paid the price for the spate of infringements.

"I'm trying my best but it's over eagerness, mate," Hooper told the referee.

An unprecedented fifth successive home defeat looked a distinct possibility before three tries in 10 minutes - to Dean Mumm, Ned Hanigan and Folau - suddenly earned the Waratahs a comfortable 24-11 lead at the break.

And the Tahs went on with the job with another four second-half tries to Folau, Hooper and replacements Damien Fitzpatrick and Bryce Hegarty.

With the axe hovering over the Melbourne franchise as the ARU plots to cut either the Victorians or the Western Force, the loss may well have been the last sighting of the Rebels in Sydney.