'What the hell': Australian Open rocked by stunning mid-point walk-off

The only thing more stunning than Aslan Karatsev's victory over Grigor Dimitrov at the Australian Open on Tuesday was the way in which Dimitrov surrendered the third set.

The world No.114, Karatsev became the first player in 53 years of professional tennis to reach the last four of a major on his grand slam debut.

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The Russian continued his fairytale run with a 2-6 6-4 6-1 6-2 quarter-final triumph over a wounded Dimitrov on Tuesday.

After looking comfortable early and winning the first set, Dimitrov was hampered by a back issue and looked a shadow of his usual self.

At 1-5, 15-40 in the third set, Dimitrov served the ball and simply walked off the court mid-point before Karatsev hit a winner straight past him.

“There’s not much point playing like this,” Todd Woodbridge said in commentary for Channel Nine.

The 18th seed called for the trainer but was seen apologising to his entourage as his physical demons continued in the fourth.

Fans and commentators were left equally stunned by Karatsev's insane run, as well as Dimitrov's sad capitulation.

Karatsev re-writes history at Australian Open

The 27-year-old Karatsev is only the fifth qualifier to make a grand slam semi-final, joining the great John McEnroe, Aussie Bob Giltinan, Belgian Filip Dewulf and countryman Vladimir Voltchkov in the history books.

"It's an unbelievable feeling, of course. The first time playing a main draw, first time playing the semis. It's incredible," he said.

Dimitrov, a former Open semi-finalist himself, looked like stopping after losing the third set but valiantly - and forlornly - continued on after receiving treatment.

But Bulgaria's one-time World No.3 could barely move at times and his return to Rod Laver Arena for the last set was merely a stay of execution.

Dimitrov was shattered at the timing of his injury.

"It's been a while that I've been to a quarter-finals, so I really liked my chances," he said.

"I felt great. I didn't see any of that coming. It was like one of the first times that I actually felt that well at a slam.

"I haven't lost a set, moving well, serving well. I felt like finally all the components were kind of coming through without doing any extra effort.

"I actually don't know what else to say. It sucks. Again, it's sport. That's why you have to keep on trying to the end.

"I give respect to the guy, as well. He saw me struggling and he kept on doing what he had to do. That's it."

Dimitrov said the injury struck "out of the blue" on Monday.

"I just got a back spasm yesterday at some point, and that was it," he said.

"We couldn't fix it on time. It happened, I think, early in the match. It kept on progressing, and it was unstoppable. But that's enough about me. It's his day."

with AAP

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