Number one seed Rafael Nadal bowed out of the Australian Open whilst unseeded players Elise Mertens & Kyle Edmund booked their places in their first ever Grand Slam semi-finals with big wins. As ever we wrap up all the big talking points from day nine at Melbourne Park. 

Marin Cilic is into his second Australian Open semi-final after world No.1 Rafael Nadal retired with a leg injury during a titanic quarter-final battle on Tuesday evening.

Cilic, the world No.6 and former US Open champion, won 3-6, 6-3, 6-7 (5/7), 6-2, 2-0 in 3hr 47min on Rod Laver Arena when Nadal retired in pain early in the fifth set.

Up next for Cilic is Kyle Edmund became only the fourth British man to reach the Australian Open semi-finals in the post-1968 Open Era with an impressive win over world No.3 Grigor Dimitrov. 

The unseeded Edmund, ranked 49, won 6-4, 3-6, 6-3, 6-4 in 2hr 49min on Rod Laver Arena. Edmund became only the sixth British man to make the last four at a Grand Slam. It also marked his first victory against a top-five ranked player. 

Elise Mertens continued her incredible winning run Down Under after the unseeded Melbourne Park debutant blew away world number four Elina Svitolina 6-4, 6-0 to reach her first Grand Slam semi-final.

World number 37 Mertens, who is yet to drop a set, retained her Hobart title earlier this month and is on a 10-match unbeaten run in 2018 after becoming the first Belgian to make the last four since Clijsters in 2012.

Mertens made all the initial running against Svitolina, returning aggressively and mixing up her game cleverly, taking every opportunity to approach the net and cut off Svitolina's passing avenues. She secured the opening set 6-4 on the back of 16 winners and taking nine of 12 points at the net.

Mertens completed the humbling of the fourth seed in 1hr 13min and will face either second seed Caroline Wozniacki or unseeded Carla Suarez Navarro for a place in Saturday's final.