Sinner has breezed into last-four on home soil in his first tournament back after doping ban
The British No1 won just two out of eight break points as Alcaraz battled to the end
Alcaraz rescued six of eight break points on the day as Draper struggled to find finishers
British number one eyeing another deep run after reaching the final in Madrid last week
The British No1 came from a set down to see off the impressive Frenchman
Djokovic has lost in the first-round in four of his past five tournaments