Richie Porte and his climbing rivals have a Willunga storm brewing for Patrick Bevin and Daryl Impey.
The Australian cycling star joined Canadian Michael Woods (EF Education First), Dutchman Wout Poels (Team Sky) and New Zealander George Bennett (Jumbo Visma) in a break on the sharp Corkscrew climb, the key feature of Friday's fourth stage.
They were caught on the fast 5km descent to the finish at Campbelltown, with Impey outsprinting Bevin (CCC Team) for the stage win.
Impey, the defending champion from South Africa who rides for the Australian Mitchelton Scott team, now trails Bevin by seven seconds overall with two days left.
But the Queen Stage at Willunga always confirms the Tour champion and Porte (Trek Segafredo) has won there for the last five years.
Friday's turning of the screw shows he has three fellow mountain goats who can work with him on the second of the two climbs to the summit finish.
"For us guys who cooked off the front there, it's good signs for Sunday," Porte said.
The four climbers all trail Bevin by 21 seconds, so the equation for one of them to win overall is that he must win at Willunga on Sunday for the 10-second time bonus and then finish 11 seconds ahead of the New Zealander.
The must put time in Impey and Bevin, who are all-rounders.
There was plenty of action in the last pulsating kilometres of Friday's stage, with Poels (Team Sky) initiating the attack by the four climbers.
Then on the descent, Porte had a brief speed wobble and managed to stay upright.
It immediately had onlookers with hearts in their mouths, remembering his crashes in stage nine at the last two Tours de France.
"Woodsy was right underneath me there," Porte said of the EF Education First rider.
"He was shouting 'no brake', but 'no brakes' doesn't really make sense, when he is right underneath you to be shouting that."
Porte also found it interesting that the chase group of 17 riders caught the lead quartet so soon on the descent.
"I was surprised to see there was a camera motorbike sat right in front of them there," Porte said.
"That's a part of it I suppose but hats off to Daryl. He is a good guy and I think he rode a great race."
Impey dedicated his win to family friend Justin Bitter, his wife's cousin, who died earlier this month from a heart attack.
Impey (Mitchelton Scott) aims to become the first rider in the Tour's 21-year history to successfully defend his title.
Australian Associated Press