What happened? We might not ever truly know. Tennis fans will get reasons, and those might be hollow. What is true is that Cincinnati Open fans did not get the high-end performance between Carlos Alcaraz and Jannik Sinner that they expected.
From the beginning of the match, Alcaraz dominated. This is nothing new for the Spaniard, but having a match so one-sided against Sinner is. Both are the best in their sport, and that will likely stay that way for years. But on Monday in Cincinnati, things went thud.
Something was clearly off about Sinner. He dropped his first service game at love. He was broken again in the third game of the first set and then broken again in the fifth game. By this point, Alcaraz led 5-0, and fans could assume the match would be decided with what happened in sets two and three.
Jannik Sinner forced to retire against Carlos Alcaraz in the final of the US Open
But the ATP No. 1 wasn't grinding away. He was flailing. He understands he can defeat Alcaraz, but almost always, the matches are close. Not this one. It was going in such favor to Carlos Alcaraz that clearly there was something off with Sinner.
In his post-match runner-up speech, he admitted he was not feeling well on Sunday (coincidentally, the day after his 24th birthday), and whatever was ailing him went into Monday. A weakened Jannik Sinner, or any player, is going to face a merciless fate against Alcaraz. He is the player 1B on the ATP tour for a reason.
Sinner decided to retire down 0-5 as continuing the match would have been pointless, especially as the US Open begins next week. There was no reason to risk wearing himself out.
The good part for tennis fans is that Jannik Sinner appears not to be injured, but simply ill. He should be fully healthy in his first match at the US Open. What fans missed at the Cincinnati Open, they are likely to see in New York. Carlos Alcaraz and Jannik Sinner should be expected to be the final at the US Open, as both players are much better than anyone else on tour.