The 23-time grand slam singles champion stuns two players during walk with fiancé Alexis Ohanian.
Federer won his first Grand Slam title in over four-and-a-half years at the Australian Open in January.
Toni Nadal will not be part of Rafael Nadal's coaching team in 2018.
The 35-year-old secured his 18th grand slam in Melbourne in January.
EXCLUSIVE: Andy Murray's former coach tells IBTimes UK greats have lots more to offer.
Federer, Nadal, Djokovic and Murray have won among them 49 of the 56 Grand Slam titles since 2004.
Federer is playing for the first time since his won the 2017 Australian Open.
Federer and Murray will make their return to tennis since the 2017 Australian Open.
Kyrgios lost to Jo-Wilfried Tsonga 7-6, 2-6, 6-4.
Wawrinka and Dimitrov join Rafael Nadal and Andy Murray in the tournament.
Nadal is easily one of tennis' greatest ever players.
Peter Fleming believes Spaniard will be unsettled by the announcement of Toni Nadal's looming exit.
Federer says he has put in too much work to leave now.
Toni Nadal announced recently that 2017 will be his last as Nadal's head coach.
The inaugural Laver Cup will commence in September 2017.
Djokovic dropped to number two in the rankings at the end of 2016.
Tsonga came back from a set down to win 4-6, 6-4, 6-1.
Dimitrov has already played 18 matches in 2017.
Andy Murray, Tomas Berdych and Boris Becker have also praised Federer's performance in Melbourne.
Sharapova tested positive for meldonium at the 2016 Australian Open.
With 18 grand slam titles and a record spell as world number one the Swiss is regarded as a sporting legend.
The Spaniard's uncle will focus on coaching in Nadal's academy after responsibilities dwindle.
Federer and Nadal faced each other for a record ninth time in a Grand Slam final.
Becker also claimed that the more Federer wins, the more he will want to play.
Berdych says he can't tell if he was good or bad in his 6-2, 6-4, 6-4 loss to Federer.
Bedene had defeated Istomin earlier in the ABN Amro World Tennis tournament.
Dimitrov's win on home soil is his second title in 2017.
The lyrics 'Deutschland über alles' are closely associated to the horrors of Hitler's Third Reich.
Toni Nadal created history by winning 14 Grand Slam titles as a coach with Rafael Nadal.
Williams is now one Grand Slam away from tying Margaret Court's record of 24.