Caleb Ewan won the opening stage of the Tour Down Under for the second straight year ©Getty Images

Australia's Caleb Ewan triumphed in the first stage of the Tour Down Under for the second straight year, as high temperatures led to a shortened route as racing got underway.

The Orica–Scott rider also won the pre-event criterium and the first stage of the 2016 edition of the race, the curtain raiser of the International Cycling Union (UCI) WorldTour season.

He repeated that feat by triumphing at the conclusion of today's stage from Unley to Lyndoch, which was shortened by 26.5 kilometres to 118.5km due to searing heat in Adelaide.

While temperatures reached more than 40 degrees, Astana’s Belgian rider Laurens De Vreese attempted to heat up the early racing on the road by launching a solo attack after three kilometres.

He remained the lone leader until the race reached is final 20km, with the peloton preparing for an intermediate sprint.

Australia’s Jay McCarthy, winner of a stage and who briefly led the general classification at his home race last year, triumphed in the sprint, giving him three bonus seconds.

The 24-year-old Bora-Hansgrohe rider will be looking to establish himself as a contender for the overall crown this year, having taken the best young rider prize in 2016.

He did not manage to triumph at the conclusion of the stage, which ended in another sprint after late breakaways from Jan Bakelants of Belgium and Australia's Adam Hansen were snuffed out in the last five kilometres.

Ewan came out on top in a time of 3 hours 24min 18sec after the Australian timed his sprint to perfection to edge out Team Sky’s Dutch sprinter Danny van Poppel.

The opening stage of the Tour Down Under was shortened due to searing temperatures ©Getty Images
The opening stage of the Tour Down Under was shortened due to searing temperatures ©Getty Images

Ireland’s Sam Bennett, runner-up to Ewan in the pre-event People’s Choice Classic criterium, was left to settle for third on the stage after a lead-out by his Slovakian team-mate Peter Sagan, the reigning world and WorldTour champion. 

"Everyone felt the heat out there today and to have the race shortened a little bit is what we needed," Ewan, whose bonus seconds see him lead the overall classification by four seconds from Van Poppel, said. 

"I'm super happy to get that win because it was very tight in the end.

"A lot of riders ran out of gas in the lead out in that last straight because there was a lot of head wind there.

"Many riders misjudged it and it was a super messy sprint."

Ewan will look to defend his Ochre leaders’ jersey tomorrow, with a 148km medium mountain stage set to take place from Stirling to Paracombe.