Naomi Osaka Blames Sickness for First Loss of 2026

The offseason is notoriously short for tennis players. That was especially true for Naomi Osaka, who spent most of December traveling the globe for exhibition events.

According to Osaka, she was sick over Christmas, and that was to blame for her first loss of 2026. Maria Sakkari defeated Osaka in straight sets at the United Cup on Friday as Japan took on Greece: 6-4, 6-2.

Media and fans alike questioned Osaka's inconsistent play throughout the match. However, it was clear that the 28-year-old did not feel well as she was seen coughing at times during the 98-minute loss.

Strong season start 🚀@mariasakkari starts her 2026 campaign with a 6-4 6-2 win over Osaka, putting Greece in front 1-0 against Japan 👊#UnitedCup pic.twitter.com/zBi8tIY9wF
— Tennis TV (@TennisTV) January 2, 2026

"I mean, honestly, from my end, it's tough to say like I don't care because I do care. I kind of have been dealing with some health stuff, so I'm kind of just happy to be out here right now," Osaka told reporters. "It's not like serious, but yeah. I was pretty happy with the level of playing that I played at right now, so whatever."

She explained, "I'm not operating at the percent that I want to be operating at, which kind of sucks because, like, I had a really good off-season, so I thought I was going to do really well here. Then I got really sick. I think I'm at the tail end of that, but still not amazing."

"So yeah, I feel like for me, I'm just trying to get better every day. Obviously, I had a cough, like a runny nose, like all that nasty stuff, yeah. Hopefully, it goes away before the Australian Open. Honestly, it's been a minute, which is why I'm shocked that I still have it. I think I got it from my daughter. I want to say like before Christmas Eve."

Sakkari 🇬🇷 64 62 Osaka 🇯🇵 (T. Sweeney 🇦🇺) #UnitedCup pic.twitter.com/Oi97ueAQbt
— ATP Tennis Stats; Snooker Stats (@ATP_Entry) January 2, 2026

As for Osaka's serving woes, the four-time Grand Slam champion could not blame illness. "Yeah, I definitely wouldn't blame that on being sick. I was just really nervous, so my hand was shaking a little bit. That's definitely from my end that comes the first match of the year, or if I have a long break or something," explained Osaka.

Sakkari explained her mindset entering the first match of 2026: "You're always very hesitant when you come in that first match because sometimes you can trick yourself that you had a good preseason, and then you have high expectations to come out and do everything," Sakkari said to reporters after the match.

"I really forced myself not to think like that. I think that was the key. Just went out there, tried to do the things that I worked on and, you know, we keep building, and we can keep trying to improve."

Using slices, dropshots, I really liked what I saw from Maria today. Let’s see how she does against Raducanu next…🙃 pic.twitter.com/DYVXTp2j3l
— Camille (@tenniscamfr) January 2, 2026

Sakkari and Osaka now have a head-to-head record of 3-3. Even better for Sakkari, she gave Greece a 1-0 lead in its tie against Japan.

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