An extraordinary obsession with numbers is at play in a large cupboard lined with cardboard boxes within the Centre Court complex.

Close to stockpiles of tennis balls held on shelves marked 3, 5 and 7, Ball Distribution Manager Andy Chevalier sits eyeballing a screen of all 18 Championship courts, monitoring each live score for multiples of nine.

In the world of mathematics, nine is a magic number (remember that tip when learning times tables, whereby the single digits of multiples of nine always add up to nine?).

In professional tennis, nine is equally magic, being the number of games played before a change of balls (balls are changed after the first seven games of a match to allow for warm-up).

The basic remit of the Ball Distribution team is to ensure there are enough balls on match and practice courts each day. Chevalier’s nightmare is the BBC announcing that there are no balls on Centre Court.

“I spend a lot of time looking at the scores and counting the number of ball changes – 6-3 here, 5-4 there – so I can be sure there will be enough fresh balls,” he says. “If there’s a particularly long match in action, I’m scanning it.”

The introduction of the final-set tie-break has helped: 18 cans is the most that can be used for a five-set match, 10 cans for three sets. The legendary 2010 John Isner-Nicolas Mahut slogathon required 42 cans of balls in their historic 11 hours and 183 games of play.

Contrary to the impression given by Wimbledon’s super-efficient ball boys and girls, only six balls are ever in play on a court. As they get struck, the balls lose pressure and get fluffier and therefore less aerodynamic.

When you see a server looking at the balls provided by the BBGs, only to discard a few, it’s not because they are seeking a lucky ball, the one they just struck a winner with. They are trying to identify those which have been least hit. ‘New balls, please’ is music to the ears.

Chevalier oversees the potential distribution of 58,752 balls ordered for The Championships from Slazenger, the Official Supplier since 1902. That is 19,584 cans, each containing three balls.

Every morning his team delivers 72 cans of balls to Aorangi’s practice courts. They also deliver 21 cans to each Championship court, and further supplies to the Indoor Tennis Centre, the Referee’s Office in case players have a hit on the Championship courts, and to a front office where the BBGs swap used balls for 10 cans of fresh balls.

So far, so straightforward. But now we get to the 3, 5, 7 business. “Imagine a doubles match on Court 14, which is open on four sides to the outside world,” Chevalier says. “They are very likely to lose balls during a match and while a member of the public happily wanders off with their souvenir, the BBGs only have five balls in rotation instead of six."

The umpire then selects the most appropriate replacement ball from the court’s designated 3, 5, 7 tin, in which there are balls that have been played for approximately – you guessed it – 3, 5 or 7 games.

When it comes to the weather, Chevalier likes extremes: a 100 per cent dry programme or a full day of the wet stuff. Nightmare No.2 is on-and-off rain with multiple suspensions of play, because if players are off the court for more than 15 minutes, they need to warm up again when play resumes. But not with fresh balls.

That means lots and lots of cans of ‘5’ balls. Chevalier has a standby store of 36 cans of those, which would suffice for two rain delays on each court on any one day. 

When he’s not juggling numbers inside Centre Court, Chevalier works as an actor. “There’s a lot of crossover with my two jobs,” he says. “Wimbledon is one big production and ball distribution is part of the invisible, behind-the-scenes team making sure the spectators enjoy the show.”

It’s all about cameras, action, roll! And providing punters with a good encore, in the form of cans of used balls, which are available to buy.

“It’s genuinely the best souvenir you can buy on-site because all proceeds go to the Wimbledon Foundation and does tremendous good,” says the ball supremo.

New this year:

See the draw like never before, with interactive Path to the Final view of the draw by clicking a player’s name on the draws page

See the projected Path to the Final of every player in the Gentlemen’s and Ladies’ singles draws with IBM Likely to Play

View how favourable or difficult a player's draw is, with IBM AI Draw Analysis