The defending champion NSW Waratahs face a fight to make the Super Rugby finals after crashing to a 32-18 home loss to the Stormers.
Resuming after an Easter weekend bye, the Waratahs were off their game on Saturday night, conceding four tries and a bonus point to the visiting South Africans while slipping to 10th on the table.
Stormers upset Waratahs in SydneyThe defeat leaves the titleholders seven points adrift of Australian conference leaders the Brumbies entering the halfway point of the competition and with plenty of work to do to remain in touch of the top six.
The haphazard display had unhappy fans filing out of Allianz Stadium before fulltime and not even the second-half return from injury of star centre Adam Ashley-Cooper could spark the Waratahs.
Uncustomary handling errors from star backs Kurtley Beale and Israel Folau and loose passing from Will Skelton thwarted their attack, while the usually reliable Bernard Foley had an off night with the boot.
He missed three from five shots, including one penalty goal attempt from in front of the posts, while the Waratahs scrum was twice pinged for collapsing and also pulled up for one of the forwards apparently standing up.
But with Michael Cheika serving a suspended ban and walking a fine line after being formally warned for approaching South African referee Jaco Peyper during his side's last-start win over the Blues, there was no chance of the coach seeking any scrum tips mid-match on this occasion.
Despite their troubles, the Waratahs snatched a 15-13 halftime lead through tries to wingers Taqele Naiyaravoro in the 13th minute and Rob Horne seconds before the break.
Naiyaravoro's five-pointer was most impressive, Folau brilliantly reeling in an over-the-top cut-out pass from Skelton one-handed before setting his big winger free on a Jonah Lomu-like surge down the sideline.
The Stormers had led 13-5 at one point after three penalties from five-eighth Demetri Catrakilis and a try to winger Damian De Allende in the 21st minute.
The visitors regained the lead six minutes after the break when Kurt Coleman's imaginative chip kick from inside his own 22 bounced beautifully into the arms of Jacobus Van Wyk and the winger raced 70 metres to score.
Foley slotted a penalty to cut the Stormers' advantage to 20-18 but it was game over when De Allende intercepted the No.10's errant pass to bag his second try 10 minutes from fulltime.
Fullback Cheslin Kolbe clinched the Stormers' bonus point with a late long-range strike.
Triumphant Stormers coach Allister Coetzee felt the Waratahs may have been "short of a gallop" after the bye, but Cheika refused to blame the fortnight between games as any excuse.
"I just think we played poorly. Particularly in the second half we were just very poor," Cheika said.
"We just didn't do the things that we do normally and you pay when that happens."
Cheika lamented his side's inability to cope with the Stormers' relentless defensive pressure.
"They try to hold you up with two-man tackles so we knew we'd see a lot of numbers in the line," he said.
"But if you want to break that, it's not rocket science: you've got to run hard, straight."
The loss piles the pressure on the Waratahs to knock over the table-topping Hurricanes next Saturday in Wellington.
The Stormers' victory ended a frustrating run of three straight defeats, but Coetzee felt his side regained belief after almost toppling the undefeated Hurricanes last start.
"I'm very satisfied with the result," he said.
"In all departments, it was a good performance from our side.
"We've been desperate this week to get things right."