Carlos Alcaraz suffered a major injury scare during his first-round match at the 2025 Japan Open on Thursday (September 25). Although the Spaniard was eventually able to get through his opener in straight sets, his post-match comments don't inspire confidence.Alcaraz, who is making his debut in Tokyo this week, seemingly rolled his left ankle in the first few games of his first-round outing against World No. 41 Sebastian Baez. The reigning US Open champion subsequently sat in the middle of the court and clutched his face in pain. Medical personnel eventually came and tended to the issue, following which the 22-year-old completed a routine 6-4, 6-2 win in one hour and 21 minutes.During his on-court interview at the Ariake Coliseum afterwards, Carlos Alcaraz admitted that his ankle felt so bad that he was unsure about continuing the match. He also expressed hopes of being physically fit enough for his next match against Belgium's Zizou Bergs."I was scared. I'm not gonna lie. I felt my ankle and didn't feel great. I'm just happy to be able to play after that. I will try to be ready for the next match," Carlos Alcaraz said. "It was unlucky. In the first five minutes I thought I wouldn't continue."The newly minted World No. 1 has now won 15 of his last 16 matches on the ATP Tour, with his lone defeat in the last two months having come to Taylor Fritz at the Laver Cup. He will be eager to secure his first title at the 500-level event, as it can end up being instrumental in his race against archrival Jannik Sinner for the year-end top singles ranking finish.Carlos Alcaraz last suffered an injury at the Barcelona Open this AprilCarlos Alcaraz retrieves a ball at Barcelona Open | Image Source: GettyDespite his haul of seven singles titles this year, Carlos Alcaraz has been somewhat unlucky with injuries. Having struggled for form in the first three months of the 2025 ATP Tour season, the Spaniard picked up a right adductor injury during his title-match defeat to Holger Rune at the Barcelona Open in April.The then-World No. 3 was consequently forced to sit out of the Madrid Open, which he had won in 2022 and 2023. Fortunately, he was able to regroup in the following weeks, securing his first-ever title at the Italian Open before a successful title defense at the French Open in May.Alcaraz's claycourt season set the tone for his grasscourt and hardcourt form as he finished runner-up at Wimbledon before enjoying back-to-back triumphs at the Cincinnati Open and the US Open.