Britain's Joe Salisbury and his American partner Rajeev Ram sealed their place in the last four of the ATP Finals doubles as they continued their 100% winning record in Turin.

Cabal and Farah fought back but Salisbury and Ram won 7-5 2-6 11-9.

Salisbury, 29, and 37-year-old Ram won all three of their group matches.

The US Open champions, who lost in the ATP Finals last four last year, will play Croat top seeds Nikola Metic and Mate Pavic in the semi-finals on Saturday.

"We knew even though we won our first two matches, we weren't guaranteed to go through, so had to go out and win again," said Salisbury, who has been managing a back injury.

Salisbury is the only Briton to reach the semi-finals in the season-ending event.

Jamie Murray and his Brazilian partner Bruno Soares have not progressed from the same group as Salisbury and Ram, while Cameron Norrie - a late alternate in the singles - cannot reach the last four even if he beats world number one Novak Djokovic later on Friday.

Norwegian debutant Casper Ruud qualified for the semi-finals - where he will face defending champion Daniil Medvedev - after fighting back to beat Russia's Andrey Rublev in a 2-6 7-5 7-6 (7-5) win.

Meanwhile, Great Britain's group matches at the Davis Cup Finals will be played behind closed doors in Innsbruck after Austria announced a full national Covid-19 lockdown starting on Monday.

Britain play in the Austrian city against France on 27 November and the Czech Republic on 28 November.

"We are very sorry for the tennis fans, who have been looking forward to this event for months now. We know the importance of fans for a competition like Davis Cup," said Enric Rojas of Kosmos Tennis, which jointly organises the Davis Cup Finals with the International Tennis Federation.