Disc brakes were first introduced into professional races at the start of 2016, but that trial was suspended after Movistar rider Fran Ventoso alleged that he had been injured by a disc rotor in a crash at Paris-Roubaix.
>> Save up to 31% with a magazine subscription. Enjoy the luxury of home delivery and never miss an issue <<
However the trial was restarted at the start of the 2017 season, with Boonen being the first rider to use disc brakes this year.
Boonen, who will retire after the 2017 edition of Paris-Roubaix, will ride disc brakes in all of his races this year, riding a Specialized Venge ViAS Disc at the Vuelta a San Juan, before switching to a Specialized Roubaix for the cobbled classics.