The Russian, who lost his first group-stage match to Taylor Fritz, overpowered De Minaur in Turin to win 6-2, 6-4 and leave his opponent on the brink of elimination.

Australian De Minaur will be knocked out with a match to spare if the other tie in the Ilie Nastase Group between Jannik Sinner and Fritz goes to three sets later on Tuesday.

Medvedev, who lifted the title in 2020, did not face a single break point and broke De Minaur's serve three times

The fourth seed will next face world number one and title favourite Sinner on Thursday.

Australia's Alex De Minaur hits a return to Russia's Daniil Medvedev during their match at the ATP Finals tennis tournament in Turin. AFP

"I decided not to care about it in a good way," Medvedev said. "If I lose, the season is over, if I win I have another chance on Thursday... I'll try and do the same the next match, so I don't care."

Both players battled to holds in their opening service games but Medvedev broke for a 2-1 lead and never looked back

He struck 16 winners in the first set and then lost just two points behind his serve in the second.

A break in the ninth game of the second set proved decisive and he closed out victory with another comfortable hold.

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