Nathan Haas (Katusha-Alpecin) during a hot stage 4 (Image credit: Tim de Waele/TDWSport.com)

Nathan Haas was the biggest GC casualty on another blisteringly hot day at the Santos Tour Down Under, conceding 54 seconds to his rivals and any hope of making the podium.

The Katusha-Alpecin rider came into the first GC stage of the race buoyed by recent good form and a solid team around him, but three days of racing in exhausting heat caught up with the Australian. He was seen dangling off the back of the bunch on Norton Summit and despite making it back to the main field, was forced to concede near the top. At the finish, as he sat in the shade at the anti-doping tent, Haas admitted that the conditions had defeated him but he raised questions over the safety and welfare of the riders. Temperatures peaked above 40 degrees for the second day in a row and despite organisers moving the start forward by an hour, the bunch was still riding in difficult conditions.

"I don't want to sound like a sore loser but we shouldn't be racing in conditions like that - in my opinion. It's just upsetting," Haas told Cyclingnews, before adding his congratulations to Peter Sagan, who won the stage and now leads the race.

"The guys who won, they handled the heat and people can say 'Nathan you're exaggerating here' but it's not safe to do this. You can shorten stages or start them earlier but if you're out there in temperatures that are six to ten degrees more than your body temperature is supposed to be in… it's just not a good thing for your body.

"Hats off to the guys who can suffer more than me but I didn't actually know I was in a bike race in the end. I just had my director yelling at me to stay in the cars. I didn't know where I was."

At the foot of Norton Summit, BMC Racing set the pace and the bunch rapidly thinned out to less than forty riders. Haas was seen dangling towards the rear and briefly lost contact before pacing himself back into contention. He was on the back-foot once more as the summit approached and could not follow when Richie Porte, George Bennett, and Peter Sagan were among those who charged off the front.

"At the bottom of the Norton Summit, I dropped myself on purpose and used a teammate to come back, just to avoid the first acceleration. That was planned and when we got back in we felt okay. Then we started the next part of the climb and I genuinely didn't know where I was. It's just insane."

Losing 54 seconds and finishing 36th on the stage effectively ends Haas' GC challenge. He now sits 34th overall, 1'05 down on Sagan with just two stages remaining. The best Haas can hope for is a strong showing on Willunga Hill, although his first priority will be to recover mentally and physically from a disappointing performance in a race he had high hopes for.

"It's all over. I lost a minute and it's such a shame because I put in so much work. Actually all my numbers and physiology this year have been better than any year and I was most looking forward to this stage. It is what it is, that's bike racing but today I was a big victim of the heat. My team was actually awesome and I can't thank them enough but from the early kilometres of the race I felt like it was a chaotic situation."

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