"I would want to know a man for at least two years before I'd allow him to mow the Centre Court," said Jack Yardley, 58, the head groundsman at the All England Lawn Tennis and Croquet Club, Wimbledon.

"As for marking the lines on the court, I'd have to know a man for at least 10 years. I remember the first time my predecessor, Bob Twyman, said to me: 'Right, Jack, mark that court,' I was scared stiff."

Yardley, a dapper and distinguished gentleman who looks as if he might have stepped off a Schweppes label, succeeded Twyman as head groundsman four years ago. He had been the assistant for 10 years before that. He has worked at Wimbledon for 32 years.

"My first job here was just a laborer, but they called me a groundsman," he recalled today. "I did sowing and chipping, but did I know what I was doing? Not a clue.

"I knew nothing about grass then. I know a little more now, but not too much."

About that, of course, Yardley is kidding. Grass is his passion, and he knows practically all there is to know about keeping the 15 grass courts of the All England Club - and four more which are being readied for use next year - in top shape during the strenuous fortnight of the Wimbledon championships.

"I pray to God for good weather. I think if the weather keeps on our side, this will be one of the best Wimbledon of all time," he said, glancing reverently at the fair skies that have prevailed most of the last two days.

"You know we've got money here. If it were possible to buy good weather, we would."

Yardley does buy the most modern chemicals to root out any weeds that dare infiltrate his precious grass. He prefers chemical warfare to getting down on his hands and knees, with scissors and magnifying glass, as Twyman used to do. But that does not make him any less a perfectionist.

"I do the watering by hand because I want to see where the water's going. It's an art. You can't just show the court water, you have to make sure it goes to the roots," he says.

Yardley and his wife, Gwendolyn - "she doesn't work, but I say she has the most important job at the club; she takes care of me" - live in a cottage on the grounds, adjacent to Court No. 6. What about his own grass?

"We have five little lawns. Not bad," he says . "But people expect them to be five little Centre Courts. It's tough to keep it up."

The real Centre Court is not returfed after each year's championships, as most people assume. Instead, it is soaked, aerated and lovingly raked to remove six barrow loads full of dead grass fiber. Then it is resown and given a light soil covering before winter. From spring until the championships begin again the third week in June - "from one year to the next, it seems only like Saturday to Monday," says Yardley - it is mown on alternate days down to its playing length of three-sixteenths of an inch.

But only by men Yardley has known at least two years.