The 27-year-old Russian Aslan Karatsev came to the Australian Open with three ATP wins under his belt and no top-100 appearance. Aslan had found his form following the last year's season restart after reaching three consecutive Challenger finals (two titles and one loss against Wawrinka), shifting it into Doha in January and qualifying for his first Major event.
As it turned out, Aslan has proved to be one of the players to beat at Melbourne Park, passing five rivals for the most notable Major debut ever! Ranked 114th, Aslan became the lowest-ranked Major semi-finalist following a 2-6, 6-4, 6-1, 6-2 triumph over Grigor Dimitrov in two hours and 32 minutes, entering history books and becoming the first qualifier in a Major semi-final since Vladimir Voltchkov at Wimbledon in 2000.
Grigor took the opening set with three straight breaks and led 4-3 in the second, looking good to forge a massive advantage. Instead of that, his back started to hurt, affecting his movement and strokes and allowing him to take only three games by the end of the encounter and propel the Russian through.
Karatsev hit 34 winners and 44 unforced errors, converting eight out of 11 break chances and suffering four breaks in sets one and two before taking charge against the opponent who was miles from his best and who barely left the court on his legs.
Aslan Karatsev will compete in the semi-final on his Major debut.
Karatsev broke in the third game before Dimitrov shifted into a higher gear to rattle off five straight games and grab the opener. Aslan netted a forehand in the sixth game to find himself 4-2 down, allowing Grigor to seal the opener in game eight following another basic mistake, this time from his backhand.
The Bulgarian wasted seven break chances earlier in the second set before they traded breaks in games five and six to stay neck and neck. The Russian scored another break with a backhand down the line winner at 4-4 and held at love with a service winner to clinch the set.
Struggling with an injury, Dimitrov won only six points on the return in sets three and four, looking worse and worse and giving serve away thrice in set number three and twice in the fourth to propel Karatsev over the finish line and into the last four. The Russian will now face world no. 1 Novak Djokovic or Alexander Zverev.