Djokovic is playing a grasscourt warmup tournament for the first time in seven years and looked relaxed as he walked about in the south coast sunshine on Monday.
Kerber is the latest big name to have pulled out of the Aegon Classic following Simona Halep's withdrawal with an ankle complaint.
Murray will start the grasscourt season at the Aegon Championships at Queen`s Club, where he faces British number four Aljaz Bedene in the first round.
Del Potro`s withdrawal follows that of French Open champion Rafael Nadal, who wants to rest before Wimbledon gets underway on July 3.
Bulgarian Dimitrov, the world number 12, has now reached only one quarter-final since winning his last of two titles this year back in February.
The tournament for the leading tour players aged 21 and under will feature a new scoring system, no lets, limited medical time-outs and shot clocks as the men`s governing body seeks ways to appeal to younger audiences.
Sharapova`s comeback from a 15-month doping ban will include a stop at Stanford University for the July 31-August 6 event, organizers announced on Wednesday.
Federer, building up for an assault on an eighth Wimbledon title, hadn't played since March and skipped the entire clay court season.
The 31-year-old Spaniard has had a hugely successful clay season, claiming a record 10th French Open crown on Sunday to earn a 15th Grand Slam title.
The Swiss veteran has taken the last two months off after what he described as a surprisingly successful start to the year that resulted in victory at the Australian Open and then the Indian Wells-Miami Masters double.
The ATP World Tour Finals, which features the world's top eight singles players and top eight doubles pairs, will be held at London's O2 Arena from Nov. 12-19.
Within seconds of the post being shared, fans from all parts of the world lambasted him for the distasteful message.
The unseeded Indo-American pair edged past the Belgium- Luxembourg combo 7-5 6-4 in the opening round of the Euro 660,375 grass court tournament.
The Spaniard now trails only Roger Federer (18) in Grand Slam title wins. With the French Open crown, Nadal (15) went ahead of Pete Sampras (14).
On Sunday, the 31-year-old Spaniard coasted to a record 10th French Open title, demolishing Stan Wawrinka in a brutally one-sided final which also earned him a 15th Grand Slam crown.
Ryan Harrison and Michael Venus won their first Grand Slam tennis title with a victory in the men`s doubles final in the 2017 French Open.