The Australian attacked from a group of GC contenders and rode Nairo Quintana (Movistar) and several other potential Tour de France riders off his wheel. Although the stage win escaped him, Porte is in a strong position to win his first stage race of 2018 and take a morale-boosting victory with the Tour de France just weeks away.
Two key stages remain in the Tour de Suisse, however, and after last year's finale at the Critérium du Dauphiné in which he lost the lead in dramatic fashion, Porte is not taking any chances or writing off any of his rivals.
"It's nice to take a little bit more time. Guys like Kelderman and Oomen are good time triallists, so it's good to put a bit more time into them," Porte said in his post-stage press conference.
Stage 7 sees the race tackle its second and final summit finish at Arosa, the location where Jan Ullrich cracked and lost almost two minutes in 2005, where Michael Albasini broke away to win in 2012, and where in 2002 Francesco Secchiari led home a Saeco-Valli&Valli one-two with Salvatore Commesso taking second.
Friday will be the 12th time that the climb will feature as a stage finish in Suisse, with the first dating back to 1946. Porte is well aware of the dangers that lie ahead, and that this race is far from over.
"We can't be complacent yet. We still have a hard stage tomorrow. The time trial isn't the best time trial for me but we'll take it day-by-day. I think we can enjoy today though because the team were incredible. Tomorrow isn't going to be an easy stage. There are a lot of tired legs out there and after today some of our guys will be tired tomorrow. Saturday should be a sprint stage so tomorrow, for our guys, will be the last proper time to put the work in, in order to defend."
The 34-kilometre time trial on the final day will ultimately decide the overall classification. Assuming Porte retains his current lead he should have enough of a buffer to hold off Kelderman, Oomen and the rest of his rivals for the yellow jersey. In his post-race press conference, one journalist asked Porte about his 'fear' ahead of the time trial. The question was met head-on.
"I remember you came to the bus this morning and you were worried if I could time trial but I've done a lot of time trials this year," he said.
"Kelderman is a good time triallist. He's a bigger guy and a flatter time trial suits him more than it does me. I've done time trials this year. You were worried that I wouldn't be able to ride my time trial bike. I can ride my time trial bike. I'm giving you an answer. I was third behind Rohan Dennis in the nationals, so I've done plenty of time trial stuff this year. Tomorrow is going to be hard, and of course, you want to give respect to guys like Oomen and Kelderman, so you try and take a bit more time on them. It's going to make it a bit easier for me come Sunday."
The journalist perhaps had a point. Porte was off the pace in two of the time trials he competed in earlier this year but they were both after bouts of sickness. At the Tour de Romandie in April, Porte turned things around with third place in the uphill individual test from Ollons to Villars.
Porte's main opposition lies on the road, not the press room, and on stage 6 he and his BMC Racing squad were forced on the defensive when a group of 18 attacked on the road to Gommiswald.
The day's early break fragmented on the final climb towards the line with Søren Kragh Andersen the last man standing. The Dane held on to take the win, with Nathan Haas and Gorka Izagirre rounding out the top three. Porte's acceleration drew several riders from the main field, including Quintana, but the Australian's out of the saddle attack soon distanced his rivals. He caught several of the fading riders from the early break but had to settle for sixth on the line in Gommlswald. The main priority was to take time on his rivals and Porte now has a healthier buffer than he did at the start of the stage.
"Stefan Küng knows the climb well and he said I could take good time. With one kilometre to go, I tested the legs a little bit. I didn't feel super but Allan Peiper said to me on the radio 'if you've got the gas you've got to go'. With 500m to go I thought that I'd made a tactical mistake but I could hear on the radio that guys were cracking behind me so of course from then on it was 100 per cent to the line," Porte said.
The sight of Quintana buckling under the pressure to match Porte and then waiting for the rest of the GC group was a telling one. No one with genuine hopes of winning the Tour de France would arrive at Suisse with their best form, and Porte acknowledged that the Colombian – and every Tour contender for that matter – still had time to improve.
"It's a good five weeks until those final Tour stages. Nairo has a little bit to improve on but then again let's see tomorrow. For me, personally, I'd love to win the Tour de Suisse and to do what I did today, they're good signs for tomorrow as well. It's nice to be able to ride guys off your wheel but I don't see too much from that ahead of the Tour."
Whether Porte goes on to win the Tour de Suisse will be somewhat immaterial in under a month, when the very best riders in the world will be fighting for the Tour de France title. The Australian held up his former teammate, and current holder of all three Grand Tours, Chris Froome, as the man to beat.
"100 per cent. Team Sky can put three teams together for every Grand Tour and have a super strong team there. We've seen Geraint Thomas win the Dauphine last week, which was brilliant to see. He's a good guy but Froome obviously smashed the Giro. Hopefully, he turns up in July a little more tired than normal. He's the defending champion, he's won the Vuelta and the Giro. If he comes to the Tour he's going to mean business."
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