Top seed Alexander Zverev crashed out in the second round of the Stuttgart Open, losing to world number 170 Dustin Brown.
Brazil right back Danilo has been ruled out of the rest of the World Cup after suffering ankle ligament damage in training on the eve of Friday's quarter-final against Belgium.
Petra Kvitova completed her preparations for an assault on a third Grand Slam title in triumphant style on Friday by downing fellow Czech Karolina Pliskova 7-6, 7-6 to win the Sydney International title.
Novak Djokovic will begin his Australian Open title defence against Frenchman Jeremy Chardy, while reigning women's champion Sofia Kenin meets wild card Maddison Inglis, following the draw for the year's first Grand Slam on Friday.
ormer world number one Andy Murray showed some more positive signs in his injury comeback but eventually went down in a bruising battle with Italy's Fabio Fognini.
India's Rohan Bopanna and his Pakistani partner Aisam Qureshi crashed out of the US Open after going down fighting in the men's doubles first round contest at the Flushing Meadows in New York.
Bidding for a record-extending ninth Australian Open title, the world number one and double-defending champion remains the runaway favourite at his favourite Grand Slam where he once remarked that he felt touched by the "divine".
Italy sealed a place in the semi-finals of the ATP Cup by winning both singles matches against France
Playing his first match since injuring his knee at Indian Wells last month, Nadal showed no signs of rust as he raced into a 5-0 lead in the first set on Court Rainier III.
Making a stupendous start to the fresh season, Ramkumar Ramanathan scalped higher-ranked Roberto Carballes Baena to set up a second round clash with tournament-favourite Marin Cilic at the inaugural Tata Open Maharashtra, in Pune.
Novak Djokovic and Roger Federer notched up contrasting victories to reach the Shanghai Masters quarter-finals on Thursday while David Ferrer fought back from a set down to knock out Andy Murray.
World champion Marc Marquez underlined his dominance of MotoGP when he swept to a record-equalling 12th pole position of the season on a good day for Spain at the Australian Grand Prix on Saturday.
Maria Sharapova's mix of grit and power were enough to see off American teenager Sofia Kenin 7-5, 6-2 in the third round of the US Open on Friday.
PHOTOS from the Wimbledon Championships matches played at the All England Lawn Tennis and Croquet Club, London, on Saturday
Roger Federer began his 63rd consecutive Grand Slam tournament with a majestic 6-1, 6-3, 6-3 first-round win over little-known Bosnian Damir Dzumhur at Wimbledon in London, on Tuesday.