Collingwood, Port Adelaide and Fremantle have joined Richmond in the AFL's crisis ward after suffering damaging losses on Sunday.
The Magpies were jumped early by Melbourne at the MCG and never recovered, eventually going down by 35 points in what was a 12th defeat in their past 15 games, a record that dates back to midway through the 2015 season.
The Power were on the receiving end of a record 86-point drubbing by surging Greater Western Sydney in Canberra.
And pre-season premiership fancies Fremantle are one of just two teams yet to register a victory in 2016 after falling 31 points short against unbeaten North Melbourne, who went one game clear atop the ladder.
With Richmond also in deep trouble after being hammered by 68 points by West Coast on Friday night, the season has been turned on its head after just four rounds.
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"It's a tough competition - what we think we know about it has been undone every game we see," said Collingwood coach Nathan Buckley.
"You don't rate St Kilda? Well they play alright.
"You don't rate Melbourne? They play alright.
"You rate us? We haven't played that well.
"You rate Port Adelaide? Two years ago they're a top-four side so (apparently) they're just going to come back.
"They get smacked by the side that lost to the side that just beat us."
Power coach Ken Hinkley says his team have produced the worst two displays of his tenure in the space of three rounds - with the 22.19 (151) to 9.11 (65) humiliation by the Giants coming hot on the heels of a 58-point reverse in the Showdown.
"Is it our worst performance? I don't know that I want to separate both performances three weeks' apart," he said.
"We were equally as bad."
The Power sit in 11th spot on the ladder with a 2-2 record and a poor percentage ahead of a huge home game against fourth-placed Geelong.
"We've just got to be ready for the battle," said Hinkley.
"If we're not, we'll find ourselves in a difficult position again."
The demise of Fremantle has been even more mystifying.
Having begun the season with genuine hopes of breaking their premiership duck, the Dockers are one of only two clubs - along with Carlton - yet to taste success in 2016.
No team has come back from an 0-4 start to qualify for the finals.
Brisbane broke their duck on Saturday with an emotion-charged 14.23 (107) to 14.10 (94) win over previously unbeaten Gold Coast.
The Lions stood firm in the second half after ruckman Stefan Martin was knocked out cold by a brutal bump from Suns defender Steven May.
Adelaide confirmed their top-four bona fides with a high-standard 16.17 (113) to 15.13 (103) triumph over Sydney.
Hawthorn coach Alastair Clarkson conceded his team got out of jail for a second straight week after the three-time defending champions edged past St Kilda by three points in Launceston.
The other round-four victors were Geelong and the Western Bulldogs.
