Emma Raducanu’s US Open victory down to grand slam’s unique balls, claims Ashleigh Barty’s coach

Still wondering how Emma Raducanu managed to lift the US Open title at the age of 18, despite coming into the event without a single win on the WTA Tour? The answer is balls, according to Ashleigh Barty’s long-serving coach Craig Tyzzer.

“So I think you see the result at the US Open [last year],” said Tyzzer, as he spoke to the media after Barty’s Australian Open triumph on Saturday night. “It was two players who, you go, ‘Wow, that was, two different players won that?’ There's no surprise when the ball is like it is.”

All the big tournaments use different balls, which annoys the players but helps generate extra income for the organisers. As Andy Murray said in 2011: “If you asked a golfer to change balls every single week, they’d be hitting shots all over the place.”

In the case of the US Open, Tyzzer suggested that the balls were very light, and thus difficult to shape through the air with different spins. His point was that Barty’s game relies on exactly those spins.

“The US Open really needs to change the ball for the girls,” said Tyzzer. “If they keep that ball the same, no one like Ash will win that tournament. And I don't know the reason why. It's the only tournament that has a separate ball for the guys and girls. So if they don't change the balls, she won't win the US Open.”

Conditions vary a great deal from tournament to tournament, and the US Open certainly played very fast in September. Neither Raducanu nor 19-year-old runner-up Leylah Fernandez hits with particularly great power, by the standards of the tour, but they are both enormously quick on their feet and press forward in the court, taking time away from their opponents.

When you combine the hot New York weather, the slick courts of Flushing Meadows