Rafael Nadal and Roger Federer took Team Europe to within two wins of lifting the Laver Cup as they won their singles and their first ever doubles rubber together in Prague on Saturday.
The world's highest ranking duo handed Team Europe, skippered by Bjorn Borg, a 9-3 lead over a Team World captained by John McEnroe after two days.
Nadal, Federer win first ever doubles rubber together
After Nadal and Federer had won their singles rubbers, all eyes at Prague's sold-out O2 Arena were then on the two legends who played on the same side of the net for the first time in careers which have stretched the best part of two decades.
They started the doubles rubber against Sam Querrey and Jack Sock on a high, earning a break in the first set to win 6-4.
They visibly enjoyed the experience, with Federer laughing off a massive air shot halfway through the set.
However, they were then in far more serious mood in the second set as both lost their serve, allowing the American pair to level with a 6-1 win.
Much to their relief, the world's top two players, with 35 Grand Slam singles titles between them, regained their composure in time to sweep their rivals 10/5 in a super tie-break which decided the clash.
Big-name pair play together after winning singles rubbers
In Saturday's opener, Federer, this year's Australian Open and Wimbledon winner and the world number two, swept 16th-ranked Querrey 6-4, 6-2 after earning a break in the first set and two in the second.
World number one Nadal, who won the French and US Open, then overcame a scare to beat 21st-ranked Sock 6-3, 3-6, 11/9.
Nadal and Sock traded breaks early into the rubber but the Spaniard added another to take the first set.
The second set was a mirror image of the first with Sock taking the honours and earning a nerve-wracking super tie-break, in which he came back from 5-1 down to level at 9-9 before Nadal showed his dominance to win.
Australia's world number 20 Nick Kyrgios then gave Team World a boost as he beat 19th-ranked Tomas Berdych of the Czech Republic 4-6, 7-6 (7/4), 10/6 in a clash of big servers.
Kyrgios lost his very first serve and struggled against the dominant Berdych in the first set, but then he took the second in a tie-break as both held on to their serves, before winning the super tie-break aided by 18 aces against Berdych's 16.
Three singles matches and one doubles rubber to finish
On Sunday, three singles and one doubles will close the tournament, with the players earning three points for each win after two on Saturday and one on Friday.
On Friday, Marin Cilic beat Frances Tiafoe, Dominic Thiem overpowered John Isner and Alexander Zverev saw off Denis Shapovalov to hand Europe a 3-1 lead as Nadal and Berdych lost to Kyrgios and Sock in doubles.