An amazing 20-shot rally inspired off-court friends Jack Sock and Nick Kyrgios to Team World's first win at the inaugural Laver Cup in Prague, Czech Republic.

The competition, named after legend Rod Laver, had raised fears of non-competitive exhibition tennis. However, judging by the standard of play on the first day, and in particular, during the aforementioned rally, such fears can be firmly laid to rest.

For server Sock was literally off his feet and lying prone on the ground after returning two shots from Team Europe's Rafael Nadal. But return them he did, with the rally finally coming to a close when a seemingly bemused Nadal dinked the final shot into the net.

The outcome saw Sock and Kyrgios coming together in a chest pump and their teammates on the sidelines off their feet amidst generous applause from their opponents. For they had simply refused to buckle in the face of a barrage of shots from Nadal and Berdych - scroll down to see the video.

The three-day tournament will be won by the first team to reach 13 points. And headed by the world's top two of Nadal and Roger Federer, Team Europe had raced into a three-point lead after the opening singles ties.

The more experienced Marin Cilic, Dominic Thiem and Alexader Zverev all won their ties, as expected, against Frances Tiafoe, John Isner and Denis Shapalov.

But the doubles pairing of Sock and Kyrgios selected by Bjorn Borg revived Team World's hopes against John McEnroe's picks of Nadal and Thomas Berdych, winning a race for the first ten points in the deciding third set.

And with two points per match-up for grabs today, Saturday, and three for each of Sunday's matches, the outcome will not be decided before the final day.

With Borg and McEnroe still to call upon Roger Federer and world number 16 Sam Querrey respectively, it promises to be a unique and intriguing couple of days for tennis fans.