Ewan originally was ecstatic after he capped a tumultuous six days by crossing the line first at Strathalbyn to claim the 149.5km stage five from Glenelg.

Minutes later, the race jury gave the stage win to second-placed Belgian youngster Jasper Philipsen - his first at WorldTour level.

Ewan disagrees with the verdict and the Lotto-Soudal leader said he had no choice but to use his head to ward off Philipsen in the run to the finish.

"You are not allowed to take your hands off the handlebars in the sprint, so I used my head to avoid ending up in the barriers," Ewan said in a team statement.

"Head movements are of course clearly visible on a helicopter shot, but a lot of former sprinters will confirm that my manoeuvre was not irregular."

The official ruling was that Ewan was relegated to last place in the front group for an irregular sprint.

Ewan, who stays in the race, was also fined 500 Swiss francs (AUD$700).

Lotto-Soudal are upset that the race jury did not hear their side of the story.

"It will take a couple of days to process the disappointment," Ewan said.

Ewan appeared to throw his head at Philipsen three times as they jostled for position inside the hectic last kilometre.

Philipsen's UAE Team Emirates squad, whose sports director is Australian Neil Stephens, had queried race officials about the incident.

New Zealander Patrick Bevin (CCC Team) bravely rode back after crashing with around 10km remaining and was with the peloton at the finish, but he was in agony.

He was taken to hospital by ambulance and it is unclear whether he will start Sunday's decisive last stage.

He leads South African Daryl Impey by seven seconds.

A group of climbers led by Australian star Richie Porte are 26 seconds behind Bevin on the overall standings.

Given Bevin's injuries, if Impey can minimise his time losses to the climbers at the crucial Willunga summit finish on Sunday, he is set to become the first rider in the Tour's 21-year history to win back-to-back titles.

Ewan started the week by winning Sunday's Down Under Classic street race.

He was then caught badly out of position in stage one of the Tour and was runner-up in stage two.

Philpsen said he was trying to hold his position when he and Ewan clashed.

"I think he hit me twice with his head ... for me it went so fast it was hard to see if it was wrong or not," Philipsen said.

Cycling fans with long memories would find it amusing that O'Grady and fellow Australian great Robbie McEwen were sitting side-by-side in the TV commentary, analysing the Ewan incident.

At the 2005 Tour de France, McEwen was relegated from third place in stage three after a clash with O'Grady.

McEwen denied he had head-butted O'Grady.

Australian Associated Press