Six players currently inside the world's top 20, including defending champion Andy Murray, have signed up for this year's Aegon Championships at Queen's Club in west London.
Also in the field is 2012 winner Marin Cilic, who came close to retaining the title 12 months ago when he reached the final only to lose in three close sets to Murray.
Cilic, now ranked No 27, is joined in the line up by Tomas Berdych (6), Jo-Wilfried Tsonga (13), Grigor Dimitrov (14), Kevin Anderson (19) and Ernests Gulbis (20).
Murray, as usual, will be the main attraction as the 26-year-old chases a fourth title at the venue in six years.
The tournament, which starts on June 9, marks the debut as a tournament director of Ross Hutchins, who replaces Chris Kermode in the post.
Hutchins said: "The entry list includes current champions such as Andy Murray, established stars like Lleyton Hewitt and exciting young talent in Grigor Dimitrov, Ernests Gulbis and Dominic Thiem, among many others.
"They will compete for a trophy that has been lifted in the Open era by Rod Laver, John McEnroe, Boris Becker and Pete Sampras. We can't wait for the tournament to get under way."