Sinner, Alcaraz and Aryna Sabalenka have been caught wearing fitness trackers during their matches at the Australian Open

The incidents involving Alcaraz and Sabalenka, who is also a WHOOP ambasassdor, sparked confusion as the company's devices are officially sanctioned under International Tennis Federation (ITF) rules as approved player analysis technology.

The news of Italian tennis player Jannik Sinner being asked to remove his wrist device comes as Carlos Alcaraz was also ordered to remove a similar device on Sunday. Alcaraz, like Sinner, attempted to

Carlos Alcaraz and Jannik Sinner have both fallen foul of an unusual rule at the Australian Open. The 2026 tennis season kicked off last week with the first Grand Slam of the year taking place in Melbourne, Australia. Heading into the tournament, Sinner and Madison Keys were the singles defending champions.

All you need to know about how a busy day in the Australian Open including a code violation, a bizarre forfeit and the banning of one of sports' most popular trackers

Tien, 20, routs Daniil Medvedev to become the youngest American man to reach a Grand Slam quarterfinal since Andy Roddick at the 2002 U.S. Open. Top-ranked Carlos Alcaraz ousts Tommy Paul. Aryna

Carlos Alcaraz remains unbeaten at the Australian Open, coming through another tough test to see off Tommy Paul and book his place in the quarter-finals. So far, Alcaraz hasn’t dropped a set through his first four matches,