David Ferrer has taken a wild card into Hamburg, after having been bothered by a stomach injury during the grass court season.
The clay-court tournament had offered a wild card to Rafael Nadal, but said the Roland Garros champion decided to take a break following Wimbledon.
Hamburg enjoyed some of its best attendance since becoming a 500 event when Roger Federer decided to play there a year ago, following his second-round exit at Wimbledon.
Ferrer will be the top seed at the tournament.