Roger Federer is beginning his grass season in Stuttgart for the third consecutive year after reaching the 2016 semi-finals.
Djokovic revealed he felt "great" after beating world number five Dominic Thiem 6-1, 6-4 at the Kooyong Classic.
Seven-time champion Roger Federer reached his 11th Wimbledon final on Friday
Wimbledon 2017 highlights: Seventh seed Marin Cilic will play 18-time Grand Slam champion Roger Federer in the men's singles final at Wimbledon after the Swiss beat Tomas Berdych in straight sets on Friday. Cilic quelled Sam Querrey's challenge in four sets to reach his first Wimbledon final.
Novak Djokovic was trailing 7-6, 2-0 and felt he had no option but to call it quits as the pain, from an injury that has troubled him for more than a year, began to increase.
Czech world number 15 Berdych, the 2010 Wimbledon runner-up, goes on to face Roger Federer or Milos Raonic for a place in Sunday's final.
Novak Djokovic will face the Czech Republic's Tomas Berdych on Wednesday for a semi-final spot, boasting a 25-2 career record over the 2010 Wimbledon runner-up.
Should Roger Federer win Friday, there is a chance he will play Sunday's final against long-standing rival Rafael Nadal, who faces Italy's Fabio Fognini in the other semi-final.
Stan Wawrinka defeated Viktor Troicki to set up a meeting with Spaniard Roberto Bautista Agut for a place in
Novak Djokovic's path to the gold has already been eased by the withdrawals of top 10 players Roger Federer, Stan Wawrinka, Milos Raonic, Tomas Berdych and Dominic Thiem
Andy Murray beat Milos Raonic to win his second Wimbledon title while World No.1 suffered a shock loss to Sam Querrey in the third at the All England Club
Andy Murray, who had won the men's singles title at Wimbledon in 2013, defeated Czech Republic's Tomas Berdych in straight sets, 6-3, 6-3, 6-3, to book a place in this year's final, where he will face Roger Federer's conqueror Milos Raonic
Andy Murray sent off his Czech rival Tomas Berdych 6-3,6-3,6-3 to set up a title showdown with Canadian Milos Raonic at the All England Club. Catch highlights of Andy Murray vs Tomas Berdych semis match here.
Andy Murray and Roger Federer will be aiming to avoid a slip-up ahead of their crucial semi-final matches against Tomas Berdych and Milos Raonic respectively
Second seed Andy Murray will face Czech 10th seed Tomas Berdych on Friday in what will be his 20th semi-final at the Majors.
Tomas Berdych is one win away from reaching his second Grand Slam final, six years after losing to Rafael Nadal in the Wimbledon title match
Tomas Berdych called for more player power in deciding whether to carry on playing in fading light
Agnieszka Radwanska, who reached the Wimbledon final in 2012, overwhelmed Kateryna Kozlova 6-2, 6-1 in just over an hour Wednesday to move into the second round at the All England Club