Dominic Thiem booked his spot in the Paris Masters third round on Wednesday by edging out Milos Raonic in a marathon encounter, while Greek star Stefanos Tsitsipas also progressed.
Fifth seed Thiem had to dig deep to get past Raonic 7-6 (7/5), 5-7, 6-4 as the Canadian powered down 30 aces in a thunderous serving display.
But Thiem, who has lost the last two French Open finals to Rafael Nadal across Paris at Roland Garros, saved nine of 10 break points to stay with his opponent before clinching the crucial breakthrough in game nine of the deciding set.
"It was unbelievable today, his serve," admitted the Austrian after winning in two hours and 38 minutes.
"He served almost all his serves between 205 (kph) and 230. When you have your chances you feel under so much pressure because you know you won't have many."
"It was already for me a horrible draw in this round and it won't get any easier from here."