As revealed by Tennis Insights, the Brazilian’s second set was, in terms of performance, the best set lost by a tennis player since these measurements have existed.

The better you play, the greater your chances of winning. Put like that, it seems like a blatant truism. But it is the theory behind Tennis Insights, a platform that measures the value of a performance using an algorithm based on ATP data. It examines four parameters: quality of shots (serve, backhand, forehand), points won on attack (aggressiveness), from disadvantageous situations (i.e., turning a rally around from a defensive position), and conversion of opportunities (coolness in decisive moments).

By adding up and weighting the indicators, a final “score” ranging from 0 to 10 is calculated. For example, Alcaraz, in his match against Rinderknech, in which he dominated the second and third sets, received a very high “performance rating” of 9.69 in the decisive set. It is impressive that Joao Fonseca, defeated in two sets by Jannik Sinner, recorded a performance rating of 9.42 on Tennis Insights in the second set. This is the best rating ever recorded on the platform for a lost set. It also prompted the Italian to praise him openly: “Now I’ve played him, I can say he’s going to do great things.”

performance—  Fonseca had made it clear that he would take to the court with the intention of beating Sinner. And these were not empty words. The Brazilian played on equal terms, even reaching three consecutive set points in the first set. His shots, especially his forehand, were clean and effective, worthy of the best players. But in the second set, Joao, who combines aggression and athleticism in his recovery, did even better. He closed the gap on Jannik and played at a level that would have earned him at least the set against almost anyone else. An above-average performance both on tour (7.29) and over his last 52 weeks, a 7.01 due to a few too many slips. But against Sinner, who averages 9.01 on Tennis Insights, the Brazilian was forced to go beyond his limits.
data—  Looking at the numbers, it was a practically perfect match for Fonseca. What stands out is Jannik’s strength, who, despite the Brazilian’s 9.42 in the second set, found the keys to go ahead 5-2. He then ended up in a tiebreak only after a break made up almost entirely of winners by the Brazilian. They call him “little Sinner” for a reason: he has very high peaks of performance, comparable to those of an absolute top player, which highlight a potential that is yet to be discovered. Eleven winners and nine unforced errors, 69% of points won with his first serve and three more points in total than the Italian in the second set, as well as the extreme coolness to take advantage of his first break point opportunity. This is how you can achieve near-perfect performances, serving at an average speed of 204 km/h. Excellence in all aspects of the game, as demonstrated by the Brazilian’s average performance of 8.32 in the first three rounds won at Indian Wells.

investiture—  But, as much as the numbers define Fonseca’s power and completeness in both attack and defense, Sinner’s words after the match are further evidence that the Brazilian’s trajectory could be definitively on the rise. “Joao definitely has qualities similar to mine,” he reflects, “he likes to take shots, he’s very aggressive and has a great mentality. He’s definitely going to be very difficult to beat. He’s already very difficult to beat now, but in the future he’ll be even more so. I think he’s a really high-quality player. He has everything it takes to be an even more incredible tennis player than he already is.” Take Sinner’s word for it. He knows a thing or two about outstanding performances on Tennis Insights and players who are difficult to beat (62-1 on hard courts against non-top 20 opponents since the start of 2024).