Rafael Nadal of Spain serves against Karen Khachanov of Russia on Tuesday in Madrid, Spain. Photo: VCG

Rafael Nadal instigated a Spanish comeback against Russia in the Davis Cup on Tuesday by capitalizing on a raucous home crowd to beat Karen Khachanov in straight sets.

Nadal, who will finish the year as world No.1, came through a second-set tiebreaker to defeat Khachanov 6-3, 7-6 (9/7) and level the Group B match in Madrid.

Marcel Granollers and Feliciano Lopez then won the deciding doubles rubber 6-4, 7-6 (7/5) against Khachanov and Andrey Rublev, who had earlier given Russia the lead with a 3-6, 6-3, 7-6 (7/0) win over Roberto Bautista Agut.

A new format this year means the Davis Cup takes place in one venue, across a single week, with organizers - among them Barcelona soccer player Gerard Pique - hoping a tighter schedule will revitalise the prestigious trophy. 

The three stadiums at the Caja Magica were all far from full for Tuesday's early matches but Nadal enjoyed a bumper crowd of local fans for his hard-fought contest in the evening.

"The atmosphere was amazing," said Nadal. Asked about the success of the competition so far, he added, "It is difficult to answer today. Let me wait until the tournament is over to have a clear and better opinion."

The last doubles match finished at just before 2:00 am, with Spain due to be back in action against Croatia on Wednesday afternoon.

"The only negative in my opinion is we are just starting the last match and it's 12:45 am," Nadal said ahead of the doubles. 

"That means big trouble for us the players and also for the people who have come to the stadium too, because tomorrow is a workday. It makes everything difficult."

Australia's Nick Kyrgios said he was ready to lead Australia to glory in the tournament after they overcame Colombia.

Kyrgios battled past Alejandro Gonzalez 6-4, 6-4 and Alex de Minaur defeated Daniel Galan 6-4, 6-3 before John Peers and Jordan Thompson also won the doubles.

"I haven't played that much in the past couple of months but I took time off to get ready for this event," Kyrgios said afterwards.

"I think we can win it for sure. The way that Alex is playing and I know I can beat every single person in this competition."

Canada are through after Vasek Pospisil and Denis Shapovalov won singles ties against Reilly Opelka and Taylor Fritz respectively to secure victory over the US while France had earlier survived a scare, the tournament's top seeds needing to win a decisive doubles rubber to beat Japan.

Elsewhere, Argentina beat Chile 3-0 and Kazakhstan prevailed 2-1 against the Netherlands. 

Kazakhstan needed Mikhail Kukushkin and Alexander Bublik to win the doubles rubber 6-4, 7-6 (7/2) against Dutch pair Robin Haase and Jean-­Julien Rojer.