Unlike some of the top tennis seeds already knocked out of Wimbledon, one grass seed developed by a Bingley firm is steadfastly surviving the rigours of the grand slam tournament.

The Sports Turf Institute at St Ives, near Harden, has served an ace in delivering a specialist grass for the prestigious tennis tournament.

And the turf, which has been put to intense testing, has been given the thumbs up by bosses and players at SW19.

An expert team from the institute - official land cultivators for the event - is working hand in hand with the All England Club to keep tabs on how the grass is shaping up to the daily stresses and strains of the championships.

Johnny Perkins, a spokesman for the event which has already seen seven-times winner Pete Sampras and number-three seed Andre Agassi knocked out, said: "There are some dry patches at the back of the courts but we've spoken to the head groundsman Eddie Seaward and he says it's as we would expect for this stage of the games.

"The players haven't complained about the grass but they have said it's a lot slower on centre court.

"It was a conscious decision to harden the courts up a bit. The way the court is prepared means the ball bounces a bit higher giving players a bit more time to react.

"It looks like the game is slower but this way it encourages more rallies and results in a better game for the millions of fans watching."

Eddie Seaward, head groundsman of the courts, said the turf institute's team was making daily inspections and watering the grass at the end of each day's play.

"From the turf point of view, in preparing the courts we create conditions which are not conducive to the traditional good turf-culture practice," he said.

He said it was vital a surface was produced on which the world's top players could use their skills to the maximum.

A main element is tennis ball bounce and the soil used has 25 per cent clay.

A traditional variety of grass - creeping red fescue - was used at Wimbledon since 1877 until last year when the institute used hardy Aberelf rye grass to improve the courts' wear and tear. The major change proved so popular with the players it was back again this year.

Britain's number two women's seed Lucie Ahl, who qualified for the championships but lost in the first round to America's Meghann Shaugness, said she was impressed with the courts.

"The grass is really put through its paces and there are a few brown areas at the back but that's where it gets the most use," said the 27-year-old from Exeter, Devon.

"I played really well in the singles last Monday and thought the ball was bouncing a lot higher."