(CNN)  -- Wimbledon have confirmed plans to hold an exhibition event on Centre Court to test conditions under the new roof ahead of next year's tennis championships.

Wimbledon first unveiled plans for a retractable roof over Centre Court in 2004 with capacity increased to 15,000.

The special one-off event has been scheduled for Sunday, May 17, just over a month ahead of next year's Championships where Rafael Nadal defends the title for the first time.

Former British number one Tim Henman, four times a semifinalist at the grass-court grand slam and a member of the All England Club, has been lined up to play.

The club's chief executive, Ian Ritchie, explained the need for a pre-tournament event:

"The key thing for the new roof is the atmospherics and humidity conditions, " he told BBC Radio Four on Tuesday.

"We need to get 15,000 people inside to test the humidity. It's a roof over a grass court and it's not like a football or rugby pitch, we need it to be absolutely bone dry.

"We have to test the air conditioning and playing surface as well."

Former champion John McEnroe is also being lined up to make a sentimental return to Centre Court.

"We are looking to put together a good raft of people to come and play.

"We will probably put several matches on as we want to put on a day of entertainment and enjoyment to try to get a maximum crowd to come and see it," said Ritchie.

Wimbledon first announced plans for a retractable roof over Centre Court in 2004, with the redevelopment increasing the capacity to 15,000.

It will mean an end, on Centre Court at least, to the famous Wimbledon rain delays, which have frustrated spectators and players alike over the years, arguably costing Henman his best chance of Wimbledon glory in 2001 when he lost a protracted semifinal to eventual winner Goran Ivanisevic.
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