Dario Cataldo abandoned the Tour of Oman during stage four after more than four hours of racing into a hot, desert wind on Friday, suffering from heat exhaustion on a long day above 35C.

"After the first stage I felt the heat, but from the second stage it was hotter and hotter," he said.

Teammate Jakob Fuglsang arrived at the uphill finish on Green Mountain one minute behind stage winner Rafael Valls of Spain and now sits seventh overall, 1:10 behind Valls. Vincenzo Nibali and Andrei Grivko rode in the front group to the base of the climb to attack the peloton and protect Fuglsang.