Why is Sinner Winning Everything Yet Alcaraz Beats Him?

Jim Fawcette

Epigraph: "Tennis is not about defense anymore. 90 percent of the time they're {Sinner & Alcaraz} only playing offense."

-- Sasha Zverev

As I write this, Jannik Sinner is on an amazing winning streak. (Except vs WADA where he settled for a three-month suspension that brings him back by Rome before Roland Garros). Sinner joined Roger Federer, Rafael Nadal, and Pete Sampras as the only four men to win a major, aka 'Slam, final without facing a single, solitary break point. The Italian Carota has won 16 straight matches culminating in defending his Australian Open title, and 36 of his last 37 all on hard courts. But his lone defeat came vs his putative archrival Carlos Alcaraz. The even younger Spaniard leads their head-to-head 6-4, winning the last 3 in a row.

One explanation for Jannik's preeminence is that he's simply better at everything. Jannik's latest victim, AO finalist Sasha Zverev and world number two ranked player said, "There are 5 or 6 major factors in tennis. I'm better than Sinner at serving, he's better than me at all the rest.'

Former world number one turned tennis podcaster Andy Roddick puts it this way: "Similar to the problems that Novak in his prime presented, Roger in his prime presented, Rafa on clay which was the toughest match-up in the history of sports, trying to beat him on clay," he said on his latest Served podcast. "You can't really go through Sinner right now. He doesn't give an inch. He can hit winners off both sides and he does what you do but like better. He didn't always serve great, but now he is so consistent. He creates way more spin wide now.

"With Sinner, it's like plugging something into an algorithm and everything comes out complete… and he's adding more to his game.

Aside from what the results and our eyes tell us, what is there that we can measure that defines his success? I argue Sinner's excellence emerges from 3 areas:

• Ability to raise his game on more important points, which leads to ATP leading ability to win break points on his own serve and on his opponents'.
• Remarkable shot tolerance (whatever that is)
• Ability to hit winners from most anywhere at most any time, creating unrelenting pressure on opponents because seemingly nothing is safe.

Better on Bigger Points

A key to Sinner's greatness is his unusual ability to play better on bigger points. This is both an ability and a deliberate tactic. Now, we could have a very lengthy discussion. Federer once said after losing to Djokovic despite being up two match points when the Serb hit a huge return landing on the outside of the sideline: That "wasn't how I was taught to play."

Sinner apparently was. And he obviously can - go bigger on bigger points. Turning to Jeff Sackman who has the numbers on Tennis Abstract's "Heavy Topspin", Sinner serves bigger when he's down and slows down elsewhere:

Sackman: "At 40-love, Jannik slows down to a crawl, serving at an average speed of only 113 MPH. But at 15-30, he ramps it up to 121 MPH. And Sinner does it without paying a price: Here are Sinner's first-serve speeds at the most common point scores he faced, from highest average down. {Note: I believe these are all at the Aussie, but won't guarantee that}

(Sackman: Yes, I know it'd be nice to have 30-40, 40-AD, 15-40, and so on. But this is Sinner we're talking about. He didn't face many of those.)

Shot Tolerance

First, we'd have to agree on what "Shot tolerance" is, but the phrase seems both vague and ambiguous. As is so often true, John's Tennisplayer.net has a seminal article. Here, Elliot Teltscher wrote about a term he may have invented back in 2008. Teltscher: "What I found was that all players have a limit beyond which they don't want to play the point anymore. That point is their Shot Tolerance." My condensed interpretation, if an opponent had a higher shot tolerance, Elliot had to try to hit a winner before reaching his own limit. If his opponent had a lower shot tolerance than Elliot did, he'd wait him out.

Teltscher: "If had to play Ivan Lendl, there was no way my shot tolerance was that high. So I had to try to create something, and that's what made him so difficult. It was very hard to create something against him. He hit the ball very deep, and very solidly, and he was very fit. He didn't miss. He would hurt you if you hit short. It was very hard to find a way to get him to make unforced errors."

Today few can win by waiting out Sinner and few can hit winners against him.

Back to Sackman: "Here are the men who have won the most of these "long" rallies on hard courts since the beginning of 2024:

But how do they win long rallies – by avoiding errors (dare I use the dreaded term "Pusher"?) or do they win them with offense?

Here's where Sackman really comes up with something. He takes the normal UFE-top-ten list and adds the combined rate at which a player either hits a winner or draws a "forced' error. {Left column is percentage of unforced errors a play commits; right is the winners he hits plus the "forced" errors he draws.} The first column puts Sinners in the top group, but the second column sets him far apart.

Sackman: "Holy Sinner! The typical ATP regular hits slightly more winners than UFEs at these stages of the rally. Tien, Tiafoe, and Arnaldi are on the wrong side of the scale. Tabilo, again, is probably favored by a limited (and biased) sample. And Sinner ... well, you need to go 15 more players down the list before you find anyone who cracks as many winners as he does, and Karen Khachanov coughs up a quarter more errors to accomplish the feat."

Sackman admits or recognizes a flaw in simply analyzing how baseline rallies end: "Alcaraz's long-rally magic doesn't fully show up in the shot tolerance metric because it isn't confined to the baseline. The signature Carlitos point is a ten-stroke rally that he puts away at the net or polishes off with a drop shot. His baseline prowess isn't quite a match for Sinner, and his net skills probably rank behind those of Federer or Nadal. But has there ever been a player who could go from gutbusting rally to all-court acrobatics with such success?

"The Spaniard approaches the net half-again as often as Sinner does. He wins nearly three-quarters of points when he does so. In today's game, a mid-rally net approach has to be earned, and many strong forecourt players don't have the baseline skills to create those chances."

"Shot tolerance, then, is necessary but not sufficient. (And that's even ignoring short points. Impregnable rallying doesn't count for much when the serve is unreturnable.) Sinner earns his point-ending chances with sturdy baseline work, then converts them from the same position. Alcaraz is nearly as good at keeping the point alive, and he has more options than anybody when it comes to finishing it.

Coloring Outside the Lines (Or, So How Does Alcaraz Beat Him?)

If Sinner edges Alcaraz in the first two areas, albeit narrowly, are Alcaraz's better net skills the whole answer to their matchup?

Matt Futterman at The Athletic discovered something unusual about what happens when the two meet. First, both Sinner and Alcaraz play more winning tennis outside the court lines than anyone.

Futterman: "There is a massive difference in what happens when Sinner and Alcaraz are outside the tramlines. This supposed zone of no return is where they can show off… Across the ATP Tour, players are hitting shots outside the singles sidelines around 17 percent of the time, but Sinner and Alcaraz win around 45 percent of the points they play from there. Their opponents win around 30. From outside the doubles lines, Alcaraz wins 43 percent of points and Sinner 42. Alcaraz's opponents win around 22 percent; Sinner's around 29."

Those are great numbers, but now comes a peculiar one, the one that distinguishes Alcaraz. When the two play each other: "They are about even in their performance on points when they move each other beyond the singles line, with Alcaraz winning 36 percent of those points and Sinner 38 percent.

Outside the doubles lines, Alcaraz has a clear advantage, winning 36 percent of the points against 30 percent for Sinner. In general, their pushing each other to greater heights also forces them to lose a few points that they would win against anybody else.

Once they get in attack, they are the two best players on the ATP Tour at closing out the point. Sinner wins 74 percent of the time; Alcaraz 73.

"Against each other though, when they are pulling off their acrobatics on points that send the opponent off the court, those rates drop. However, Alcaraz's doesn't drop as much. He converts 66 percent of the time against Sinner, while Sinner converts 62 percent of the time from his end of the court."

These two players have separated themselves from the pack and are threatening to redefine ATP tennis as seemingly all-offense-all-the-time. Both are widening the court of offensive play. But Alcaraz has a slight edge at the very outer boundaries.

Sources & Further reading:

• Tennis 365 on Andy Roddick's podcast
• ATP Tour "Leaderboard" on pressure play
• Tennisplayer.net article by Elliot Teltscher, "Shot Tolerance"
• The Athletic: Carlos Alcaraz and Jannik Sinner play tennis. Their Australian Open rivals see a different sport
• Jeff Sackman, Tennis Abstract's "Heavy Topspin"
  • Yes, Sinner is Really This Good
  • The Locked-Down Serve of Jannik Sinner
  • How Does Jannik Sinner's Season Stack Up?
  • Carlos Alcaraz and the Fruits of Shot Tolerance