The 'Big 4' of tennis - Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray - are playing at the Laver Cup for the first time this weekend. The fifth edition of the team competition has been dominated by Federer's impending retirement.On Thursday, the quartet - who have a staggering 66 Grand Slam singles titles between them - hit the practice courts at the O2 in London. The 'match' was chaired by Team Europe's Stefanos Tsitsipas.Federer is set to play the final match of his illustrious career tomorrow (Friday) alongside his good friend and arch-rival Rafael Nadal. The legendary pair will take on Team World's Jack Sock and Frances Tiafoe in the fourth match on day one.Laver Cup@LaverCupA practice session unlike any you've ever seen before #LaverCup95981644A practice session unlike any you've ever seen before #LaverCup https://t.co/afhnYa0rSaFederer teamed up with Nadal while Djokovic and Murray turned up on the other side of the court. During one of the rallies, Federer was heard saying about Nadal at the net:"He's the boss tomorrow!"Here's the video of a rally between the four players:Michael Hincks@MichaelHincksSpot of Federer/Nadal v Djokovic/Murray doubles Federer moving just fine... Mainly at the net so far and a volley winner goes down a treat "He's the boss tomorrow!" Federer said moments ago of Nadal #LaverCup911145Spot of Federer/Nadal v Djokovic/Murray doubles Federer moving just fine... Mainly at the net so far and a volley winner goes down a treat "He's the boss tomorrow!" Federer said moments ago of Nadal #LaverCup https://t.co/hjeOMbg6MLThe last time Federer played doubles with Nadal was also at the Laver Cup - during the competition's inaugural edition in Prague five years ago. The duo beat Sock and Sam Querrey in a supertiebreak."Tomorrow night, my last match, doubles with Rafael Nadal" - Roger FedererRoger Federer (left) and Nadal ahead of their Laver Cup 2022 matchAfter the line-up of matches on day one of the competition got released, Roger Federer confirmed that he will indeed play the last match of his career alongside his rival and friend Rafael Nadal."Tomorrow night. My last match. Doubles with Rafael Nadal"Roger Federer@rogerfedererTomorrow night. My last match. Doubles with @RafaelNadal 🏽 twitter.com/lavercup/statu…Laver Cup@LaverCupThe line-up is set for Day 1 of #LaverCup13888118420The line-up is set for Day 1 of #LaverCup https://t.co/HnulRs01KXTomorrow night. My last match. Doubles with @RafaelNadal 💪🏽❤️ twitter.com/lavercup/statu…Roger Federer has lost three of his four doubles matches - all at the Laver Cup - since his match with Nadal in 2017. One of those losses came with his other arch-rival Novak Djokovic. Federer's only win in this period came with Alexander Zverev three years ago. In his last doubles match - also in 2019 - Federer and Tsitsipas lost to Sock and John Isner.The Swiss star's announcement means he has played his last singles match - Wimbledon 2021 quarterfinal against Hubert Hurkacz. The contest saw the 20-time Major winner suffer his first bagel set in 221 matches on grass.Federer will hope for better luck in the doubles arena - where he holds a 131-92 record over his career - as he wades off into a golden sunset. Team Europe are seeking a fifth straight Laver Cup title this weekend.Also Checkout:- Roger Federer vs Rafael Nadal Head to Head