Carlos Alcaraz and Jannik Sinner Both Break Unusual Australian Open Rule

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.

Meanwhile, the likes of Alcaraz, Novak Djokovic, Aryna Sabalenka and Iga Swiatek are looking to get their season off to the perfect start.

Alcaraz and Sinner are still on course to meet in the final, with the Spaniard set to take on Alex de Minaur in the quarter-final. Meanwhile, Sinner will face American Ben Shelton.

It has since emerged that both Alcaraz and Sinner had broken a bizarre rule at the Australian Open.

As per The Express, Alcaraz was ordered to remove his Whoop, a fitness tracking device, during his match against Tommy Paul

Although it has been claimed that the Whoop 3.0, 4.0, 5.0 and MG devices are on the ITF-approved list of player analysis technology devices, Tennis Australia stated that they are not wearable during Grand Slam events.

A statement read: "Wearables are currently not permitted at Grand Slams. The Australian Open is involved in ongoing discussions on how this situation could change."

Sinner was also asked to remove his Whoop device when he played fellow Italian Luciano Darderi.

The defending champion's device was spotted by umpire Greg Allensworth, and he removed it without complaint.

Women's world number one Aryna Sabalenka had also fallen foul of the rule earlier in the tournament.

Jannik Sinner speaks out after Australian Open rule break

Speaking about the incident, Sinner said: "These are datas what we would like to use also in practice sessions because from that you can practice on with the heart rate, how much calories you burn, all these kind of things. Yeah, I mean, the umpire asked me straightaway if this is the tracker. I said yes. He said remove. It's fine.

"There are other things we could use. It's the vest. But it's a bit for me uncomfortable. You feel like you have something on the shoulders. It's a bit different. But rules are rules. I understand. I won't use it again."

🚨 Today Sinner was also asked to remove his whoop tracker and was asked about it in press :

“We would like to track a bit on court…This is data we would like to use also in practice sessions. Heart rate, calories burned e.t.c but yeah rules are rules”
pic.twitter.com/Z7kHHB5Bxp https://t.co/GJUJTofQLb

— SK (@Djoko_UTD) January 26, 2026

However, the founder and CEO of Whoop, Will Ahmed, was far from happy.

He wrote on social media: "Ridiculous. Whoop is approved by the International Tennis Federation for in-match wear and poses no safety risk. Let the athletes measure their bodies. Data is not steroids!"

The 2026 Australian Open will take place from Monday, January 12 to Sunday, February 1. You can purchase match tickets on Ticketmaster or catch all the live action in the UK via discovery+.