Iga Swiatek came out against the tennis balls used during the US Open series of events claiming it's hard to control them.
She's not the only one who spoke out against the ball as Paula Badosa was another player that spoke out against them publicly. The reason is quite simple, both of them hit the ball really hard and the lighter balls tend to fly out of the court with so much power. For Swiatek and Badosa, it really makes a difference making it hard for them to control the balls.
Another argument is that it simply makes no sense. Why used different balls at all and that is something Alex Corretja agrees with as well:
“But now we can see that the players, the women, that they're hitting so hard, so they need to have a little bit more control. And I heard like the ball for them, it seems like it's flying because they're lighter or whatever, and they don't have that nice feeling."
He added:
“When you're a player, you need to have a feeling to play. So I think they should consider that maybe for next season, they should just play with the same ball because probably in these days where we are, it doesn't make any sense anymore to have different balls.”