Rohan Dennis upstaged BMC teammate and race favourite Cadel Evans to take the third stage of the Tour Down Under and claim the ochre leader's jersey on Thursday.
Dennis took the overall lead from fellow South Australian Jack Bobridge, who faded to finish 42 seconds back on the 143.2-kilometre stage from Norwood to the tiny town of Paracombe.
Former Tour De France winner Evans is riding his last race before retiring, with his BMC team determined that he leaves the sport a winner.
Thursday's result means BMC will now have to make some major strategic decisions on how to approach the last three stages of the season-opening UCI World Tour race.
On the first really hot day of this year's Tour, Dennis finished in 3hr 35min 8sec, three seconds ahead of Evans and Dutchman Tom Dumoulin (Giant-Alpecin).
Another race favourite, Tasmanian Richie Porte (Sky), finished five seconds behind Dennis alongside a group of riders including Frenchman Maxime Bouet (Etixx-Quick Step) and Italy's Domenico Pozzovivo (AG2R La Mondiale).
In another fascinating day's racing, Australia's Will Clarke from the local Drapac team broke away early and rode solo until he was joined by Calvin Watson (Trek Factory Racing), Lasse Norman Hansen (Cannondale-Garmin) and Axel Domont (AG2R La Mondiale).
The four stayed away for much of the race until one by one they began to feel the pinch, with first Domont and then Hansen dropping off.
Watson stayed with Clarke until 12 kilometres from the finish when he fell away, with Clarke hanging on for another four kilometres until he too was swallowed up by the peloton.
The brutal finish entailed a 1.5km climb up Paracombe Hill and all the big names were in good position at the beginning of the ascent.
- Surprise attack -
Evans attacked immediately and he was joined by Porte, Dumoulin and Pozzovivo.
With 300 metres to the summit the four were caught by the chasing group.
Dennis then took everyone by surprise when he attacked, holding on for his first individual win since he claimed the third stage of the Tour of Alberta in 2013.
Dennis later admitted he was meant to attack at the bottom of the climb to take the sting out of Richie Porte's legs.
"I was caught a bit back at the lead-in (to the climb) and I thought don't panic and don't try to go into the red zone before the hill," he said.
"The plan was for me to attack at the bottom and put the other guys under pressure and let Cadel sit back, but obviously I was a bit too far back to follow that plan.
"I saw Cadel get away with four guys so I just sat in behind one of the Movistar riders and hoped he'd bring me back.
"Cadel in my eyes is still the leader," he added. "I'm not sure how the team meeting will go tonight."
Friday's 144.5km fourth stage runs from beachside Glenelg to the Adelaide Hills town of Mt Barker.
Source: AFP