Tennis fans on the internet have slammed Jannik Sinner supporters for targeting Carlos Alcaraz for his recent comments on the Italian's doping saga. Sinner tested positive twice for Clostebol, a substance banned due to its muscle-building properties, during the 2024 Indian Wells Open.He had his ranking points and prize money deducted for a run to the semifinals in Palm Springs. But he escaped a ban by proving to the International Tennis Integrity Agency (ITIA) that the substance entered his body because of his physio Giacomo Naldi's negligence.Naldi, nursing a wound on his finger during the Indian Wells event, had applied Clostebol to the affected area and exposed the Australian Open champion to the substance during massages.Carlos Alcaraz, with whom Jannik Sinner shares a budding rivalry, was asked by the media ahead of the 2024 US Open to share his thoughts on the ITIA's decision."It’s a really difficult moment for him. It is complicated… But obviously what I can say? Well, I believe in a clean sport. So I don’t know too much about that. I am pretty sure that there are a lot of things that we don’t know inside the team or inside everything. But if they let Jannik keep playing, it’s for something, they said he’s innocent. So that’s all I can talk about," Carlos Alcaraz responded.The Spaniard's remark didn't sit well with a few Sinner fans, who denounced him on Instagram.Sinner fans attacking Alcaraz on his Instagram page byu/OctopusNation2024 intennisOther tennis fans active on Reddit condemned the naysayers and defended Carlos Alcaraz."Actually embarrassing. They think they're white knights coming to Sinner's aid against the evil Carlos. Such narcissistic behavior," one fan wrote.Comment byu/OctopusNation2024 from discussion intennis"Thing is what “aid” does he really need? He’s a professional athlete who broke a doping law by having a banned substance in his system. What are people supposed to say beyond “I believe his story and respect the ITIA decision?” another said.Comment byu/OctopusNation2024 from discussion intennisHere are a few more reactions from Reddit:"People are f**king unhinged," a fan stated."The hilarious thing is that Alcaraz didn't even really do anything lol. He gave a pretty neutral answer when asked about Sinner but by these comments you'd think he straight up called Sinner a doper or something," a fan commented."I don’t get diehard fanaticism. Like your favorite should never get any negative criticism. No criticism at all. Only positives else, let’s fight. He/she absolutely can never do any wrong. Idolatry. It’s ridiculous. where do people learn that? Lol," a fan wrote."Carlos did nothing wrong and I hope whoever in his team that manages his IG would block all these crazies' account. He doesn't deserve to have this kind of toxicity around him, especially on the night before US Open starts," a fan remarked.Carlos Alcaraz leads Jannik Sinner 5-4 in head-to-head ahead of a possible SF meeting at 2024 US OpenJannik Sinner and Carlos Alcaraz embrace each other. (Getty)Carlos Alcaraz and Jannik Sinner have played against each other nine times thus far, with the Spaniard holding a small lead of 5-4 in the head-to-head. The two notably find themselves in the same half of the 2024 US Open men's singles draw.Sinner, seeded first, will open against Mackenzie McDonald from the United States, whereas No. 3 seed Alcaraz finds himself pitted against Australia's Li Tu in the first round.There's a possibility that Alcaraz and Sinner can clash during the New York event if both of them manage to qualify for the semifinals. Notably, they have already played five semifinals against each other with the Spaniard leading the tally 3-2.Most recently, Carlos Alcaraz defeated Jannik Sinner in the semifinals of the 2024 French Open before beating Alexander Zverev in the final.