Stefan Denifl is the second rider charged with professional fraud in Operation Aderlass blood doping case Sep 24, 2019 Stefan Denifl on his way to victory on stage 17 of the 2017 Vuelta a España (Photo: Yuzuru SUNADA)Stefan Denifl is the second rider to be charged with fraud in the wake of the Operation Aderlass blood doping ring. Tags: Doping General News News Share 0 Share on Facebook Tweet Tweet on Twitter +1 +1 on Google Plus