At 7:30 a.m. each day of the Wimbledon fortnight, hours before competition begins, the keepers of the grass gather to meticulously prepare the tournament's hallowed courts for play.

Dozens of people spread out around the All England Club grounds to mow, paint and mop — yes, with a sponge mop and a pail of water, just like folks might use to make a kitchen floor sparkle. The night before, after a day's action concludes, the courts are vacuumed ("Hoovered," as the locals say) to collect whatever debris might have gathered — yes, with a larger, heavy-duty version of what folks might use to clean a living room rug. Water sprinklers are briefly turned on, with the exact amount for each court determined by measuring its hardness and what the weather is. And then the covers are pulled over.

"Tuck her in, put her to bed," said Grant Cantin, the head groundsman at the All England Club, "and see you in the morning."

This is not typical lawncare, mind you. It's a bit of well-organized and highly specialized choreography, done in an attempt to ensure that everything is just right when the likes of Roger Federer step on Centre Court. The process will happen Saturday morning well before a packed house of 15,000 or so, plus millions more in front of TVs, watch Venus Williams plays Garbine Muguruza in the women's final. And again Sunday morning before the men's final.

"We want people to walk in here and just be, 'Wow!' It's all about presentation. We want to be looking the best we can," Cantin said. "I lay in bed thinking about the grass. I'm obsessed with it."

Federer and Novak Djokovic were among the players who raised questions about the court conditions during this year's tournament.

"Everybody's entitled to their own opinion. We do try to produce the exact same court, but when we're up against heat that we've never had before, it obviously makes our life very difficult," said Cantin, a Canadian working at his 16th Wimbledon. "Overall, we're extremely happy with the way the courts have played. ... Held up remarkably well. We're just going to go on and do our job."

Djokovic pointed out what he called "a hole" in the turf at Centre Court to a chair umpire after one match. Kristina Mladenovic of France and Alison Riske of the U.S. both complained about Court 18 after each slipped early during a second-round match, when the unusually warm and dry recent weather left patches of beige-colored grass or, worse, dirt near the baselines — something that usually doesn't happen until the latter days of the Grand Slam tournament.

It's also something that never happens at the U.S. Open and Australian Open, which use hard courts, or the French Open, which is played on red clay.

"This is Wimbledon. The courts are going to be in the best shape possible," said Steve Johnson, an American who was seeded 26th this year. "But it definitely plays a little different once it gets worn. It gets more slick. The bounces aren't as pure. ... Dealing with that is part of the game."

As Cantin stood in the Centre Court stands Thursday, a three-man crew — each member in a green polo shirt, blue shorts and white sneakers — went about its daily tasks to prepare the perennial ryegrass for the women's singles semifinals.

Rick Street already had finished his job at No. 1 Court when he arrived at the main stadium shortly before 8:15 a.m. to push a yellow-and-black electric lawnmower — gas-powered versions were used until last year — from end to end, cutting the grass precisely to a height of 8 millimeters (that's less than a third of an inch; imagine a stack of eight dimes). A roller at the back of the machine pushed down the grass as it's cut; by going first in one direction, then the other, parallel to the doubles alleys, Street created the illusion of stripes.

"There's no great secret to it," Cantin said as the mower's whir filled the arena and the unmistakable smell of grass cuttings wafted about. "You need a roller on the back of the mower, and a steady hand to keep the lines straight."

The same process repeated itself all around the facility, where each year the courts are re-seeded.

"History tells us that Centre Court is the most famous tennis court in the world," said Neil Stubley, the club's head of courts and horticulture. "But from a turf perspective, it's no better or worse than any other courts."

After 20 minutes, Street removed a black bin on the back to clean out what he'd trimmed so far.

"I've always said you could sell those grass clippings," Cantin said. "Put them in a key chain or something."

As Street continued, mopper Ben Sidgwick arrived with green pail in hand. He would wet his mop, then hunch over and use its sponge to slowly skim the grass, erasing whatever slight remnants of white line paint might have been scattered about by the mower.

Finally, it was painter Will Brierley's turn. Street helped Brierly stretch a piece of orange string, just so, along a court line, then fasten it into the ground with a small metal stake. Eyes down, Brierly pushed a wheel to dispense the paint, walking slowly, heel-to-toe, heel-to-toe — first the vertical lines, then horizontal, ending at the baselines.

By now, Street's double cut of mowing was complete. Sidgwick knelt and allowed drops of mop water to drip near the lines and used his fingers to rub away excess paint from individual blades. After that, the final touch: He took a paint brush and gently dabbed the occasional blank spot along each baseline.

The mopping and touchups are important, Cantin explained, because the Hawk-Eye replay system is precise enough that even an extra speck of paint where it shouldn't be could affect readings.

"Need an absolute crisp line," Cantin said.

At 9:50 a.m., Sidgwick walked off the court, can of white paint and brush in his right hand, green pail of water and mop in his left.

The court was ready.

"By the time the gates open at 10:30, we're done, we're out of here," Cantin said, "and we're not seen."


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