Daniil Medvedev will take on Stefanos Tsitsipas in a second straight Australian Open semi-final on Friday.
The pair met at the same stage on the Rod Laver Arena last year, with Medvedev winning in straight sets.
The Russian battled from two sets down against Canada's Felix Auger-Aliassime to set up this repeat meeting with the 23-year-old Greek Tsitsipas.
Tsitipas, who had elbow surgery last last year, powered past Italy's Jannik Sinner in straight sets by comparison.
In the first semi-final 20-time Grand Slam champion Rafael Nadal will face Wimbledon finalist Matteo Berrettini.
Medvedev still the favourite
As the highest seed standing, Medvedev is arguably still the favourite to lift the title on Sunday, but was made to work hard for his semi-final berth.