It may have come just in time to give Sinner ample opportunity to banish dark thoughts. A succession of training sessions and matches kept him away from a cause that, even in hindsight, looks controversial.
Perhaps because he was number one in the world rankings, the Italian received different treatment. A suspension did not come because, according to the decision-makers, he was able to explain how the banned anabolic steroid clostebol got into his system.
He said it was to treat a small wound on his skin. His physiotherapist Giacomo Naldi and fitness coach Umberto Ferrara were fired. "The reactions of the players around me were quite positive when things came to light. Then, of course, it was discussed further, but that's how it is everywhere. I can't do anything about it today," he defended himself.
The course of the US Open then also bestowed him with two pleasant gifts in the form of early exits from his main rivals. Novak Djokovic dropped out in the second round, while Carlos Alcaraz departed in the third. And so his road to the trophy, apart from a clash with Daniil Medvedev, was not lined with many star names.
Key moments
Jannik Sinner v Mackenzie McDonald 2-6, 6-2, 6-1, 6-2
The pressure of the doping scandal was still very much felt in his first match and perhaps it affected the way the match went. Sinner faced 10 break points in the first set and lost serve three times. He lost another serve in the opening game of the second set. However, he then broke back at 2-6, 0-1 and dominated the court from then on.
Jannik Sinner v Daniil Medvedev 6-2, 1-6, 6-1, 6-4
Sinner has lost to Medvedev seven times, including a five-set duel at this year's Wimbledon. That's also why the quarter-final match was an open affair. The Russian was able to answer the lost first set with a string of five games in the second. However, he was visibly losing from the third set onwards.
Sinner broke his opponent by converting break points at 1-0 and 3-0. "This is an opponent that is difficult to play against. He has a feel for the game. Many times he picks the right shot at the right time," Medvedev, who eventually made 57 unforced errors in the match, said about the key moments of the clash.
Jannik Sinner v Taylor Fritz 6-3, 6-4, 7-5
Fritz did not fare well at all on serve in the opening stages of the final, and thanks to that, Sinner had an easy route to winning the opening two sets.
However, there was a moment in the third set that allowed the American to turn the match around. "He served much smarter after that, so I had to change a few things and my position on the return," Sinner admitted.
Fritz got the break, only to lose his serve again and his opponent didn't give him another chance. Although the aggressive American registered more winners (24-23), he also made more errors (34-21).
Key numbers
2
This is only the second Grand Slam title Sinner has won. He won both this season and both on hard courts. He also lost just two matches (versus 34 wins) on hard courts all year. The US Open is the tournament where, given his game, he will have the best chance of success.
23
Sinner became the second-youngest player to win the men's singles title at the Australian Open and US Open in one season in the Open era. He was 23 years and 23 days old on the day of his victory over Fritz.
Only Jimmy Connors was younger in 1974, and that was half a century ago. A new young generation is confirming its arrival, that's for sure.
The Italian has also won 23 matches at Grand Slams this year.
11,180
That's how many ranking points Sinner has after the US Open. In just one year, he recorded 75 wins and only seven losses. He won nine tournaments. His lead over current runner-up Alexander Zverev is 4,105 points.
The Italian became only the eighth player in history to break the 10,000-point mark. Djokovic's record (16,950) from 2011, however, remains a long way off.
Sinner showed his dominance in New York and answered the two Grand Slam titles won by rival Alcaraz. "I'm having an unbelievable year, I've really achieved a lot of big wins. It all started with the title in Australia, which gave me confidence and I'm still benefiting from that," he said in his post-match speech.
The trophy was perhaps symbolically presented to him by Andre Agassi, who has had a similarly controversial period in his career. The iconic American was also caught by doping commissioners with a positive test - in his case for methamphetamine - during his career.
However, Agassi also managed to convince the ATP that the substance had entered his system by mistake, and the organisation investigated the case and shelved it. Nothing has been released to the public since.
Sinner didn't want to talk about the case anymore after the final and was more philosophical: "I slowly rebooted myself during this tournament to feel a little bit more what I am like as a person. Not everything is perfect and because of that, I know not to stop working. It's good for the sport to have new champions."
