Casper Ruud secured the final semi-final spot at the ATP Finals ©Getty Images

Norway's Casper Ruud came from one set down to beat Russia's Andrey Rublev and secure the last-remaining semi-final spot at the Association of Tennis Professional Finals.

Ruud and Rublev encountered a simple win-and-your-in scenario, where whoever won the head-to-head would set up a semi-final with Russia's Daniil Medvedev.

Rublev sauntered through the first set, winning 6-2. before Ruud battled back, consistently winning the key points, if never dominating proceedings.

The world number eight won the second set 7-5, before claiming a final-set tiebreak to win 2-6, 7-5, 7-6.

Ruud will now play world number two and defending champion Medvedev, while world number one Novak Djokovic of Serbia will face Germany's Alexander Zverev, who defeated Djokovic on the way to his Tokyo 2020 Olympic title, in the other semi-final.

Djokovic is set to play Britain's Cameron Norrie, who replaced Greece's Stefanos Tsitsipas earlier in the tournament after the 23-year-old withdrew through injury, to close out the group stages this evening. 

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