Zverev's Sinner problem, and the one variable Madrid changes

The most generous thing said about the Madrid final this week was said by the man playing in it. "He is quite a relaxed guy and he is enjoying tennis right now," Alexander Zverev said of Jannik Sinner, after dispatching Alexander Blockx in straight sets to set up his fourth meeting of the year with the Italian. "I think tennis is very easy for him right now, the way he is playing." It is the sort of thing one player says about another when the alternative is to admit something less comfortable. Zverev, on Sunday afternoon at the Caja Mágica, will play Sinner for the ninth consecutive time without a win.

It was not always this way.

Act one: Zverev as the senior partner

The first time these two met on tour was at Roland Garros in October 2020, and Sinner, then nineteen, won in four sets. Three weeks later they met again in the Cologne semi-final, and Zverev won 7-6(3), 6-3. That second match set the template for the next three years. Zverev beat Sinner at the 2021 US Open in straight sets. He beat him at Monte-Carlo in 2022 in three. He beat him at the 2023 US Open in five. Of their first five meetings, Zverev won four. The numbers had a quiet logic. Zverev was taller, older, more experienced, and Sinner was still the player whose ceiling we were arguing about rather than measuring.

The 2023 US Open match, in the fourth round on a Tuesday night in New York, was the last time anyone watched Zverev beat Jannik Sinner. It is now closer to two years ago than to one.

Act two: the door closes

They did not meet again for almost a year. When they did, at the Cincinnati semi-final in August 2024, Sinner won 7-6(9), 5-7, 7-6(4) in a match that lasted three hours and refused to settle. That match is the start of the streak that is currently being read out in the Madrid programme.

Eight in a row. Five at Masters 1000 level. Four in the semi-finals of consecutive Masters 1000s in 2025 and 2026: Paris, Indian Wells, Miami, Monte-Carlo. Sinner has dropped just three sets across the eight, and none in the past five matches. In Monte-Carlo last month he did not face a single break point and converted all four he earned. The body of work is no longer ambiguous.

The thing about a streak is that it is the result, not the explanation. So: what changed.

What changed

Three things, mostly. The first is the obvious one. Sinner became Sinner. Through 2023 and 2024 his backhand stopped being a defensive shot and started being a weapon, his serve added kilometres without losing accuracy, and his movement, always good for a man his height, sharpened into something that no longer looked like compensation. He stopped giving away the cheap point at the back of the court and started taking the cheap point at the front of it. The room he gave Zverev to dictate, and Zverev needs room, vanished.

The second is positional. Zverev plays from a long way behind the baseline. It works against most of the tour because most of the tour does not have the depth and pace to make that distance a liability. Sinner does. The deeper Zverev stands, the longer Sinner's flat ball-striking has to do its work, and Sinner's flat ball, struck on the rise, is now the cleanest in the sport. Zverev cannot retreat from it. He cannot step up to take it earlier without rebuilding a position he has spent his career refining. He is being asked, mid-rally and mid-rivalry, to become a different player.

The third is the one nobody likes to write down. Sinner has acquired the air that Federer used to give Andy Roddick. There is no agitation in him on the changeover. The body language between points is the same body language at 5-0 as at 0-0. Zverev has spoken openly, often, about how much harder he is finding it to feel the match against Sinner as a contest rather than as something happening to him. "Tennis is very easy for him right now" is, read in that light, less a compliment than a diagnosis.

Madrid is not Monte-Carlo

The two have never met at Madrid. They have met at Roland Garros, at Cologne, at the US Open twice, at Monte-Carlo, at Cincinnati, at the year-end finals, at the Olympics. Not here. The reason matters: Madrid sits at 667 metres of elevation, and the ball, on the dry red clay of the Manolo Santana, behaves differently from the ball at any other Masters 1000 stop on the calendar. Serves go through the court. Flat shots stay flat for longer. The percentage point between a winner and a ball clipping the tape moves a few millimetres in the server's favour.

That is one of two reasons Zverev has a 30-6 record at this tournament and two titles (2018, 2021) on the resumé. The other is that he is 1.98 metres tall with one of the cleanest serves in the sport, and Madrid is the closest the clay swing comes to giving a serve-first player his proper weight.

The serve numbers, this week

Both men have arrived at the final on the back of a fortnight of almost untroubled service holds. Sinner has not faced a break point on his way through. In Friday's semi-final against Arthur Fils he won 21 of 24 first-serve points: an 87.5 per cent return that on a hard court would be impressive and on clay is borderline absurd. He has dropped two sets in the tournament. He has not been broken in any of them.

Zverev has held with the kind of efficiency the surface rewards a tall player for. Against Blockx in the semi-final he won 85 per cent of first-serve points (34 of 40) and 67 per cent on the second (8 of 12). Against Cobolli in the quarter-final he conceded just seven points behind his first serve in the entire match. Against Mensik the round before, in his only three-set scrap of the week, he won 81 per cent of first-serve points. Madrid's air, the long-rumoured friend of the big man, has shown up.

So the serving form is real, and it is mutual, and that is where the slim case for Zverev begins. If both players hold their service games at the rate they have been holding them, the match goes to tiebreaks. Zverev does not need to outplay Sinner from the back of the court for two and a half hours; he needs to win two tiebreaks. Madrid is the venue on tour where the second proposition is closer to the first.

The case for the upset, fully stated

It runs as follows. The serve is, this week, working at the level Madrid asks of it. The court is fast enough that Zverev's flat first serve forces Sinner to play returns from positions he prefers not to play them from. The altitude takes the half-step of margin that Sinner's ball-striking has used to dismantle Zverev in Paris, Indian Wells, Miami and Monte-Carlo, and gives some of it back. Hold serve. Force tiebreaks. Win one. Take the match into a third where Sinner has to think, for the first time in this rivalry in two years, about what is happening rather than about what is next.

That is the plan. It is also, very nearly, the entire plan. Because the moment Zverev's first-serve percentage drops into the high sixties, the moment a return floats and Sinner takes a second serve early, the door that has been closed since August 2024 stays closed. Sinner has converted four of four break points in their last meeting and has not given away a single one of his own. The margins Madrid offers Zverev are real but small. The margins it offers Sinner are smaller still, and Sinner has been operating on smaller margins than that for fifteen months without losing.

What we are watching for

If the first set is on serve at 5-5, Zverev is in the building. If the breaker arrives and his first-serve percentage is north of 70, the building is interesting. If Sinner is broken once in two sets, by anything other than a string of unforced errors, the conversation about this rivalry will have to be opened again, however briefly. None of those things are likely. All of them are possible. Madrid is the only stop on tour where they are even possible.

The same lens, your game

The kind of attention a touring pro pays to a serve — the tightness on the toss under pressure, the inch by which the contact point drops in a tiebreak, the half-step the returner takes before the swing is finished — is the same kind of attention they will pay to your serve, if you ask. Film a few of your service games and upload them at allcourt.club/try, and a pro from the All Court network will watch the way they would watch this final, and tell you what they see. The gap between what you think you are doing and what is actually happening is almost always where the improvement lives.

Bunnies, and how these stories end

The bunny problem in tennis, which is what this is, tends to end one of two ways. Either the trailing player wins one match in unlikely circumstances and discovers, the next time, that he was capable of winning the others all along. Or he does not, and the streak becomes a number that arrives in the post-match graphics until one of the players retires. Roddick never solved Federer. Murray solved Djokovic, twice, in the matches that mattered. Most of these stories end with the first interpretation. Some end with the second.

The Madrid air, the empty record book between them at this venue, the second serves that have stayed above sixty per cent for both men all week. There is an opening. It is the smallest one Zverev has seen in two years. Whether he is the player who walks through it, or the player Sinner reminds him, again, that he no longer is, will be answered some time after five o'clock local time on Sunday afternoon.

Either way, somebody will say afterwards that tennis is very easy for him right now. The interesting question is which one.