Diego Schwartzman knows he cannot afford to be overawed by the challenge of facing 13-times French Open champion Rafa Nadal in the quarter-finals at Roland Garros on Wednesday. The Argentine counter-puncher said it will take a very high level of tennis for him to compete with Nadal, who has won the last 35 sets he has contested on the Parisian clay. "If you think about the four, five hours you are going to play, if you think about everything about Rafa in Roland Garros, he"s very difficult to play," Schwartzman said. "You have to go on court, think about the tactics, think about how to play your best game." Schwartzman"s only win in 11 encounters with Nadal came in Rome last year. However, just few weeks later he was beaten by the Spaniard in straight sets in the French Open semi-final. However, the 28-year-old is excited about having another crack at claycourt"s ultimate challenge. "Playing against Rafa in these kinds of tournaments, it"s always a good time to know how good are you playing," Schwartzman said. "It"s always a good challenge. I want to be there one more time." World number one Novak Djokovic, having survived a huge scare in the fourth round against teenager Lorenzo Musetti, must overcome another Italian Matteo Berrettini for a place in the semi-finals. In the women"s quarter-finals, American teenager Coco Gauff bids to continue her dream run when she takes on Czech Barbora Krejcikova, while holder Iga Swiatek faces Greek Maria Sakkari.