Porte launched an attack in the final kilometre of the queen stage, which former Team Sky team-mate Sergio Henao could not follow, to claim his third consecutive triumph on the category one uphill finish and move to second overall behind race leader Simon Gerrans (Orica-GreenEdge).
“I know Sergio quite well. He was a team-mate in Sky for four years but he didn’t want to come through and give me a hand so I thought I’d give him a few good shakes and eventually I got rid of him, which is always good to look back and see someone looking down at the ground instead of stuck to my back wheel,” Porte said.
“It’s a fantastic climb for me. I was set-up great by the team, they backed me, but this climb I love. I remember doing it in 2008 in the UniSA team and waiting for Allan Davis to help him over. Ever since then I’ve enjoyed it every time I’ve been back.”
The 30-year-old at the beginning of the tour said he was uncertain of his form and felt “underdone” but showed no sign of weakness with BMC, including defending champion Rohan Dennis, committed to today’s cause.
The tour is Porte’s first race with the outfit he transferred to this season in a bid to lead a yellow jersey assault at the Tour de France.
“Full credit to Rohan. He said yesterday he didn’t have great legs and he was willing to sacrifice, which is, him being a South Australian and it’s his home race, I was so happy for that.
"He’s been a brilliant team-mate this week and to be honest the whole BMC crew has been fantastic. It’s not easy to change teams like this coming from a fantastic team like Sky but BMC they’ve really supported me and embraced me and I’m really happy,” Porte said.
“I definitely came in here underdone. I stayed in Europe until Christmas Eve so I’m really happy with how it’s gone. It’s a good stepping stone I think to probably the most important season of my career.”
A four-man break including Pim Ligthart (Lotto Soudal), Lars Boom (Astana), Juan Jose Lobato (Movistar) and Reinardt Janse van Rensburg (Dimension Data) animated the beginning of the race, working well together to achieve a maximum time gap of over six minutes during the 151.5km run from McLaren Vale to Willunga Hill, while Orica-GreenEdge and equally omnipresent Tinkoff, working for Jay McCarthy, controlled the peloton.
Janse van Rensburg was particularly aggressive in the break, attacking on the Willunga finishing circuit. The quartet was inevitably caught, however, as the finish neared.
Stage five highlights
Sky stayed vigilant throughout the day and then mobilised at the front of the peloton, pegging back the break’s advantage as it worked to position Henao, inside the final 15 kilometres. BMC then began to contribute before Orica-GreenEdge returned to the head of the bunch and the escapees were caught with about 5km remaining.
The attacks soon started with Peter Kennaugh (Sky) moving off the front, then a sharp acceleration from Simon Clarke (Cannondale) and Dennis.
The 19-year-old Lucas Hamilton (UniSA Australia) tried to make his own impression inside two kilometres to go but lost ground as Porte launched his winning effort.
Gerrans has all but won his fourth Tour Down Under title with tomorrow’s criterium finale unlikely to impact the general classification. Henao sits third overall and has won the mountain classification.
Tour Down Under 2016, stage five: McLaren Vale to Willunga Hill, 151.1km
1 Richie Porte (Aus) BMC Racing 3-34-16
2 Sergio Henao (Col) Team Sky at 6secs
3 Michael Woods (Can) Cannondale at 9secs
4 Diego Ulissi (Ita) Lampre–Merida at 17secs
5 Rafael Valls Ferri (Esp) Lotto Soudal
6 Ruben Fernandez Andujar (Esp) Movistar
7 Domenico Pozzovivo (Ita) AG2R La Mondiale
8 Simon Gerrans (Aus) Orica–GreenEdge
9 Jarlinson Pantano (Col) IAM Cycling
10 Patrick Bevin (NZl) Cannondale
Overall classification after stage five
1 Simon Gerrans (Aus) Orica–GreenEdge 17-16-31
2 Richie Porte (Aus) BMC Racing at 9secs
3 Sergio Henao (Col) Team Sky at 11secs
4 Jay McCarthy (Aus) Tinkoff at 20secs
5 Michael Woods (Can) Cannondale
6 Ruben Fernandez Andujar (Esp) Movistar at 28secs
7 Domenico Pozzovivo (Ita) AG2R La Mondiale
8 Rafael Valls Ferri (Esp) Lotto Soudal at 36secs
9 Steve Morabito (Sui) FDJ at 49secs
10 Patrick Bevin (NZl) Cannondale at 50secs
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