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Dimitrov was 5-3 down in the opening set when he was forced off, having slipped five games into the contest.

The Bulgarian received treatment on his knee during a medical timeout but moved awkwardly when he attempted to continue and only lasted 35 minutes on No.1 Court.

While the 10th seed's tournament ended in frustrating fashion, fifth seed Medvedev advances to the last eight for the second time, having made the semi-finals last year.

He will face a huge test against Sinner, who beat Ben Shelton in straight sets in his own round-of-16 match.

The world number one has won 42 of his first 45 ATP Tour-level matches of the year, becoming just the fourth player to achieve that feat this century after Roger Federer (2005-06), Novak Djokovic (2011, 2015-16) and Rafael Nadal (2013, 2018).

Medvedev has won six of his previous 11 meetings with Sinner, but each of the Italian's five victories over him have come in their last five meetings.

The 2021 US Open champion will be eyeing revenge on Tuesday.