Medvedev became only the fourth player in ATP history to beat the world's top three at the same tournament.
Former world number one Andy Murray is in line to play Grigor Dimitrov in the opening round of the inaugural ATP Cup, with Bulgaria qualifying among the final six teams in the nation-based tournament.
Andy Murray's illustrious career finally came to an end as he and doubles partner Dan Evans were beaten 6-2, 6-4 by American pair Taylor Fritz and Tommy Paul in the Olympics quarter-finals at Roland Garros on Thursday.
World No 1 Novak Djokovic was beaten by Tomas Machac in the Geneva Open semi-finals.
The American duo won 5-7, 6-1, 13-11 as they added the season-ending crown to the Wimbledon and US Open titles.
World number two Nadal's fate will rest on his final group match against Tsitsipas.
Melbourne on Friday completed 28 days since the last reported locally-acquired case of novel coronavirus infection.
Images from the men's singles action at the US Open on Sunday.
India's Sumit Nagal becomes 1st Indian to win match at Masters on clay since 1990!
However, the 33-year-old Spaniard will not know until later on Friday whether his Herculean effort was in vain.
Rafael Nadal's hopes of winning the year-ending ATP Finals for the first time live on after the Spaniard beat defending champion Stefanos Tsitsipas 6-4, 4-6, 6-2 on Thursday.
ATP events in Hamburg, Bastad, Newport, Los Cabos, Gstaad, Umag, Atlanta and Kitzbuhel will not go ahead as scheduled.
Now both men have made history for their country, leaving a permanent mark on the history books.
Kavach 3.2 version is being installed on approved high-density routes, the railway officials said, adding that upgrading and installation of the latest version on new routes will go on simultaneously to cover a wider railway network in a shorter period.
Nadal held his nerve as he was tested by the 91st-ranked Argentine
Roger Federer will make his return to the tennis circuit from a double knee surgery at an ATP 250 tournament in Qatar in March, having not played since last year's Australian Open.
World number one Novak Djokovic will not compete in the Miami Open as he tries limit the number of events he plays this year, the 36-year-old Serb said on Saturday.
India's Yuki Bhambri and his Dutch partner Robin Haase squandered three match points in the deciding set to go down against Nicolas Barrientos of Colombia and Rafael Matos of Brazil in the Australian Open men's doubles first round in Melbourne on Tuesday.
Roger Federer called for a merger between the two governing bodies last month, with both Simon and ATP Tour Chairman Andrea Gaudenzi welcoming the suggestion. But some top WTA players have said they want an equal standing for the women players in a combined body.
The winners of the Serbia-Germany tie will join Spain, Russia and Italy in the semi-finals.
The Serb set up the breakaway PTPA on the eve of the US Open in September and resigned as head of the player council but last month he confirmed that he had been nominated by his fellow professionals for the current elections which he accepted.
Australian Open holder Djokovic will make his ATP Cup debut for Serbia against South Africa in Brisbane on Saturday while Nadal will lead Spain into action against Georgia in Perth on the same day.
Swiatek downs Gauff to meet Sabalenka in Italian Open final
The ATP tour, which was suspended in March due to the novel coronavirus outbreak, is set restart on Aug. 14 with the Citi Open, followed by the Cincinnati Masters, which will be held at Flushing Meadows before the US Open.
Nishikori is the latest high-profile men's player to pull out of the season's first Grand Slam following the withdrawal of Briton Andy Murray on Saturday.
Australia's Nick Kyrgios could find himself in hot water again after accusing men's tennis governing body ATP of being "corrupt" following his US Open first round victory.
The hosts had blanked Germany in their opening tie and became the first to seal a quarter-final spot with their second 3-0 win in the inaugural team event.
Images from the US Open men's singles second round matches, at Flushing Meadows, New York, on Thursday.
Muguruza wins all-Spanish clash with Badosa at WTA Finals
Iga Swiatek and Coco Gauff stressed the need to start matches earlier at Grand Slams
Australian top seed Alex de Minaur moved into his second consecutive final at the Next Gen ATP Finals with a 4-2, 4-1, 0-4, 4-2 victory over Frances Tiafoe in Milan on Friday.
The 32-year-old debutant at the ATP's blue riband event won the first 11 games of the round-robin clash before a relieved Nishikori finally got on the scoreboard with an angled winner.
World number one Novak Djokovic began his quest for a sixth title at the season-ending ATP Finals with a 7-6(4), 6-2 victory over Norway's Casper Ruud in their round robin encounter in Turin on Monday.
'I think it only happens in France. At Wimbledon, obviously, there's not that. Or in Australia either. At the US Open, it's still rather quiet. Here, it's a really unhealthy atmosphere.'
Sumit Nagal registered a straight sets victory against Canada's Gabriel Diallo on his debut at the Miami Open.
In its probe report into the June 17 accident in West Bengal's Darjeeling district that left 10 persons dead, including the loco pilot of the goods train, the Commissioner of Railway Safety (CRS) also recommended implementation of the Automatic Train-protection system (KAVACH) on top priority.
Daniil Medvedev fired Russia into the final of the ATP Cup on Saturday with a tense 3-6, 6-3, 7-5 win over an injury-hampered Alexander Zverev after the German destroyed a racket in frustration over a lost service break.
Tabilo broke the top seed four times on Centre Court while not conceding a single break point.
The Bangalore Open scheduled to be held from September 29 has been suspended due to the local promoter's security concerns, according to the Association of Tennis Professionals (ATP) Board.
It was Sumit's second Challenger title of his career