Dennis jumped away from a small group of title contenders on the category one Torrens Hill Rd climb that featured in the last two kilometres to finish clear ahead of BMC team-mate Cadel Evans and Dutchman Tom Dumoulin (Giant-Alpecin).
The 24-year-old has a seven second advantage on team-mate Evans after the third stage with Dumoulin a further two seconds adrift in third.
"I was caught further back but I rode with no stress as Cadel was away with Richie [Porte],[Domenico] Pozzovivo, Dumoulin," said Dennis. "I stayed behind a Movistar rider, hoping that he'd bring [me] back to the front. Thumbs up to Cadel. He's a man of little words but we've done well together today."
"To be honest, I didn't expect to win. The plan was for me to attack at half way into the climb but I was too far back to follow the plan."
Excess salt on jerseys was indication of a hot day for the peloton after milder conditions earlier this week.
Will Clarke (Drapac) was the first rider to escape after the start in Norwood with Lasse Norman Hansen (Cannondale-Garmin), Axel Domont (AG2R La Mondiale) and Calvin Watson (Trek) joining the Australian within the opening 15km to comprise the main break.
The quartet achieved a maximum time advantage of about three minutes and thirty seconds but, on what was tipped to be a decisive day for the GC, they were inevitably reeled in.
Domont was the first to lose contact with the lead group as the sun and sting of upward, winding roads took a toll. The gap to the three leaders quickly started to fall within the final 25km as Sky again contributed to the pace-making. Hansen and then Watson dropped back as Clarke persevered before being caught inside the last 10km as Giant-Alpecin aimed to provide Dumoulin with a lead-out to the base of the climb. The attacks commenced on the climb with Dennis benefiting from the element of surprise as others watched Evans. He won the King of the Mountain prime, 400m from the finish, on his way to stage honours.
Team Sky’s Richie Porte couldn't match the sprint of his rivals in the final and is now fourth overall, 15 seconds in arrears of the leader. He will look to stamp his authority on the race during Saturday’s penultimate stage to the always decisive Old Willunga Hill.
“BMC is in a good position but I don’t think it is all over just yet,” Porte said. “Willunga is a totally different style of climb.
“Cadel was strong with a few little attacks [today] ... I still think it’s all for him,” he said. “We will see how it plays out on Willunga. BMC is a man down and that is not going to make it easy. They’re going to have to control the race now, which they haven’t done thus far, so we’ll see.”
Tour Down Under 2015, stage three: Norwood to Paracombe, 143.2km
1. Rohan Dennis (Aus) BMC 3-35-08
2. Cadel Evans (Aus) BMC at 3 secs
3. Tom Dumoulin (Ned) Giant-Alpecin
4. Maxime Bouet (Fra) Etixx-Quick-Step at 5 secs
5. Michael Rogers (Aus) Tinkoff-Saxo
6. Richie Porte (Aus) Sky
7. Jack Haig (Aus) UniSA-Australia
8. Rubén Fernandez (Spa) Movistar
9. Domenico Pozzovivo (Ita) AG2R La Mondiale
10. Simon Geschke (Ger) Giant-Alpecin at 13 secs
Overall classification after stage three
1. Rohan Dennis (Aus) BMC 10-17-06
2. Cadel Evans (Aus) BMC at 7 secs
3. Tom Dumoulin (Ned) Giant-Alpecin at 9 secs
4. Richie Porte (Aus) Sky at 15 secs
5. Jack Haig (Aus) UniSA-Australia
6. Rubén Fernandez (Spa) Movistar Team
7. Michael Rogers (Aus) Tinkoff-Saxo
8. Maxime Bouet (Fra) Etixx-Quick-Step
9. Domenico Pozzovivo (Ita) AG2R La Mondiale
10. Daryl Impey (RSA) Orica GreenEdge at 22 secs
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Sophie Smith is an Australian journalist, television reporter and presenter, who has provided coverage for Cycling Weekly from races across the world. She has covered eight Tours de France, as well as reporting for national and international newspapers as well as other magazines.
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