Australian Thanasi Kokkinakis and Britain's 2011 semi-finalist James Ward have been handed wildcards into next week's Queen's Club pre-Wimbledon event.
Both have been sidelined for lengthy periods due to injury and are hoping to kickstart their returns on the grass of west London.
The field is headed by five-time winner Andy Murray, world No.3 Stan Wawrinka and Milos Raonic - the 2016 runner-up to Murray. Others include Grigor Dimitrov, Australian Nick Kyrgios, Marin Cilic, Jo-Wilfried Tsonga and Tomas Berdych.
The event suffered a blow when Argentine Juan Martin del Potro and Britain's Dan Evans had to pull out due to injury.
Del Potro is dealing with a groin problem which had troubled him at the French Open while Brit Evans is suffering a calf injury.
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"James and Thanasi have had a difficult time with injuries over the last year or two and we are delighted to give them a chance to play," tournament director Stephen Farrow said.
"We all remember James in the 2011 semis. Thanasi is one of the most-talented young players in the sport and it's great to see him back."
The tournament draw will be made on Saturday.
