World number three, Grigor Dimitrov has been knocked out by British rising star, Kyle Edmund, ranked 49, same day debutant Elise Mertens downed Elina Svitolina, world number four.
Edmund, ranked second in Britain after Andy Murray beat the Bulgarian in thrilling four sets 6-4 3-6 6-3 6-4 in the first quarter final of the day.
He has now reached the semi-final of a Grand Slam for the first time in his career.
With the win, he is projected to break the top 30 for the first time at around No.25. He now faces the winner of Rafa Nadal vs Marin Cilic for a place in the men’s final.
“Reaching the last stage of the best tournament in the world it’s obviously very pleasing, but of course I want to keep going,” Edmund said in a court side interview.
The South African born Briton is 23 years old. As a junior player, he won two junior Grand Slam doubles titles, at the 2012 US Open and the 2013 French Open, both with Portuguese partner Frederico Ferreira Silva. He was also was part of the Great Britain team that won the Junior Davis Cup for the first time in 2011.
Dimitrov had beaten Edmund only two weeks ago in the quarter-finals at the Brisbane International, but there was no repeat.
“It’s an amazing feeling. I’m very happy,” said an overwhelmed Edmund, ranked 49 and in his first semi-final at a major.
“It was a hard match and I’m really trying to enjoy the moment. It was my first match on Rod Laver Arena and it’s very special.”
The 23-year-old is the only British man in the draw after Andy Murray’s injury withdrawal before the tournament, raising the prospect that it will be him, rather than the Scot, who breaks through to win in Australia.
Murray has been a five-time finalist, but lost them all.
Dimitrov now joins Novak Djokovic as one of the top seeds to be beaten by unheralded players. Djokovic on Monday was stunned by South Korean player, Hyeon Chung in three sets.
On Tuesday, Dimitrov was not the only top seed blown off court. Unseeded Australian Open debutant Elise Mertens downed world number four Elina Svitolina in straight sets Tuesday to reach a first Grand Slam semi-final.
The Belgian world number 37, on a 10-match unbeaten streak after winning in Hobart this month, knocked out the Ukrainian 6-4, 6-0 in 1hr 13min.
Mertens, who is yet to drop a set, is the first Belgian to make the last four since Kim Clijsters in 2012.
“I’m lost for words. I don’t know what to say. I just gave my all today,” she said. “I played my game today and tried to stay aggressive.”
Mertens, 22, trains with her coach and boyfriend Robbe Ceyssens at the Kim Clijsters Academy in Belgium and has seen her world ranking rise from 127 at the end of 2016.
She had never been beyond the third round of a Grand Slam before in four appearances.
“He means a lot,” she said of the importance of Ceyssens.
“He’s by my side all the time. Since we have been together my game has only gone upward. All credit to him.”
Mertens made all the initial running, returning aggressively and mixing up her game cleverly, taking every opportunity to approach the net and cut off Svitolina’s passing avenues.
She broke the world number four in the third game and then again for a 5-2 lead.
Serving for the set, Mertens tightened and a double fault on break point handed the Ukrainian a way back.
Mertens still had a second chance to serve out. Another double fault allowed Svitolina a glimmer at 15-30, but Mertens composed herself and landed three first serves to secure the set 6-4.
The Belgian had powered 16 winners to Svitolina’s eight and significantly won nine of 12 points at the net.
Svitolina was immediately in trouble at 0-40 at the start of the second.
She saved those but a weak forehand into the net gave a fourth and Mertens landed an overhead smack on the sideline to secure the break.
Another break followed, and a third courtesy of a sumptuous backhand pass took Mertens to the brink of the last four at 5-0.
She completed the humbling of Svitolina with little fuss and will face either second seed Caroline Wozniacki or unseeded Carla Suarez Navarro for a place in Saturday’s final.
If she makes it she will emulate Clijsters, who won at Melbourne Park in 2011.
Mertens had a message for her countrywoman and tennis great who she said would be following the match in the middle of the night back home.
“Kim, thanks for watching and don’t get too stressed.”