Gallery: US Open day eight

While one half of the draw appears to be wide open, the other is laden with stars. Rafael Nadal marched into his first quarterfinal in four years at Flushing Meadows, where he will face Russian teen Andrey Rublev. Meanwhile, Kaia Kanepi’s dream run through qualies continued. These are the best photos of the day.

: Madison Keys roared back from a set and a break down to beat Elina Svitolina 7-6(2) 1-6 6-4. Photo: Getty Images

: Svitolina needed to reach the semifinals to stand a chance of taking world No.1 at the end of the tournament. Photo: Getty Images

: Keys trailed by a break in the decider, before battling through to the win. Photo: Getty Images

: Federer lost just 13 points on serve during the match – and didn’t face a break point. Photo: Getty Images

: Roger Federer was in cruise control during his fourth round with Philipp Kohlschreiber, winning 6-4 6-2 7-5. Photo: Getty Images

: Rafael Nadal was an easy 6-2 6-4 6-1 winner over Alexandr Dolgopolov. Photo: Getty Images

: Alexandr Dolgopolov was unable to stay with Nadal through much of the match. Photo: Getty Images

: Nadal is through to his first US Open quarterfinal in four years. Photo: Getty Images

: Andrey Rublev became the youngest US Open quarterfinalist since Michael Change in 2001 with his straight sets win over Goffin. Photo: Getty Images

: David Goffin was supposedly injured prior to his fourth round against Andrey Rublev. Photo: Getty Images

: CoCo Vandeweghe was a 6-4 7-6(2) winner over Lucie Safarova. Photo: Getty Images

: Safarova enjoyed a solid return to form after struggling in the last couple of months. Photo: Getty Images

: Vandeweghe is one of three Americans through to the US Open quarterfinals in the women’s draw. Photo: Getty Images

: In what proved to be an epic comeback, Juan Martin del Potro downed Dominic Thiem 1-6 2-6 6-1 7-6(1) 6-4. Photo: Getty Images

: Juan Martin del Potro fought back from two sets down against Dominic Thiem. Photo: Getty Images

: After taking an easy couple of sets, Dominic Thiem struggled as Juan martin del Potro found his form. Photo: Getty Images

: Delpo appeared to be ill during the opening couple of sets, but recovered as the match went on. Photo: Getty Images

: Kaia Kanepi became just the second qualifier to reach the US Open quarterfinals in the Open Era. Photo: Getty Images