Polish tennis star Iga Swiatek drew harsh boos during her match Friday when she aggressively hit a ball toward a ball boy in frustration. Swiatek faced Russian 17-year-old Mirra Andreeva in the ...

Other tennis fans were even more scathing of Swiatek’s behaviour. One author posted: “Swiatek literally hitting a ball back at a ball kid. Poor sportsmanship and dangerous play. I’ve never ...

What are tennis balls made of? Modern tennis balls are made of a hollow rubber core, covered in a wool or nylon shell which is known as the nap. Pressurised air inside the rubber core makes the ball ...