Just as Porte has an iron grip on the general classification, fellow Australian Ewan is ruling the sprint finishes.

Barring disaster, Porte will win the Tour for the first time.

And even when he is on the back foot, Ewan showed again yesterday that he is the fastest man in this year’s race.

Ewan was eight riders back and apparently out of contention at the top of the finishing straight in stage three.

But the 22-year-old sprint ace blasted past his rivals at Victor Harbor for his second stage win of the Tour and his fifth for the year.

Two-time defending world champion Peter Sagan had his best result so far this week, finishing second.

“It was definitely satisfying, it’s got really really hectic in the end,” Ewan said.

“In the last kilometre I thought I was too far back and luckily I made my way up for the sprint.

“I was a bit further back than I hoped.

“Sometimes you have to hold tight and try not to waste too much energy.”

Ewan grinned broadly and tapped his chest as he won.

“I don’t know – I’m thinking of different salutes to do,” he replied when asked about his finish-line gesture.

Sagan noted that this is January and Australia – far removed from the top sprint fields that Ewan will face in Europe.

But Orica-Scott team director Matt White said it was a good sign that Ewan was out of position and lacked a couple of teammates, but still found a way to win.

Porte finished safely in 19th place, exorcising the ghost of last year’s Tour disaster at the same coastal town.

Then, the BMC team leader was caught out when the peloton split near the finish and he lost eight seconds.

Simon Gerrans’ overall winning margin over Porte was nine seconds.

“There’s so much to lose on a stage like this and not a lot to gain,” Porte said after yesterday’s finish.

He retained his 20-second overall lead over Spaniard Gorka Izaguirre, whose hopes of somehow overhauling the Tasmanian took another hit in a three-rider crash near the finish.

While Izaguirre lost no time, given the crash happened less than three kilometres from the finish, he suffered some nasty-looking gravel rash.

A race media release stated he had been taken to hospital “as a precaution and will have x-rays to rule out any fractures”.

“Race doctor Mark Fisher says it totally depends on his hospital assessment as to whether he will start tomorrow,” the release said.

“I saw that, it was pretty close,” Porte said of the crash.

“You don’t like to see that happen.

“I heard Izaguirre crashed there, so that’s not good either for the race.”

The Tour continues today with a 149.5km stage from Norwood to Campbelltown, with the stage looping through the Adelaide Hills, which could provide another sprint finish opportunity for Ewan.

-AAP