Real Madrid's roof will be closed against Man City: Why? What ...

Real Madrid’s match against Manchester City will look very different to the average European football match — and even to other matches at the Bernabeu.

Why? Well, on Tuesday, Madrid received permission from UEFA to close the relatively new roof for the game this evening. This will be an oddity to most football fans — only a few football-ready stadiums in Europe have retractable roofs.

But why have Madrid asked to close the roof? Does playing sports in an indoor stadium have a noticeable effect on the game compared to an outdoor stadium? And how do City feel about it?

Here, The Athletic’s Guillermo Rai, Amitai Winehouse, Mario Cortegana and Sam Lee explain the situation and what it all means.

Why have Madrid asked to close the roof?

This one is quite simple. Tuesday night’s game is huge — it’s a Champions League quarter-final first leg, and Madrid are looking for any advantage to take into the return fixture at the Etihad Stadium.

There is a thought that closing the roof improves the atmosphere in the ground. Madrid have a raucous fanbase and increasing the noise from them would benefit the team against City.

UEFA, in conjunction with match referee Francois Letexier, has approved the closing of the roof for the game. Madrid cannot open the roof once the game has kicked off, unless there is severe weather that means they have to.

When was the roof installed and have they closed it before?

Madrid have been carrying out an extensive renovation of the Bernabeu since 2019. They have increased capacity to 85,000 and improved the facilities at the ground, all for a cost that stands at €1.76billion ($1.91bn, £1.51bn).

One major addition has been the roof, which was finally ready for use at the start of this season.

Madrid have used it several times since. The first was the 2-1 win over Getafe in September, which was also Jude Bellingham’s home debut for the Spanish giants. He scored the winning goal in stoppage time.

They closed the roof for the 1-1 draw against RB Leipzig last month, which saw them advance in the Champions League courtesy of a 2-1 aggregate win. It was also shut for the 1-1 draw with Atletico Madrid in February and for the 4-1 win over Villarreal in December among other La Liga games — Madrid do not have to ask the league for permission to do so, which is a key difference to the Champions League.

Which other football stadiums in Europe have retractable roofs?

Only a handful of major stadiums in Europe have retractable roofs.

Schalke’s Veltins-Arena, Romania’s National Arena, the Friends Arena in Sweden, Vitesse Arnhem’s GelreDome, the Johan Cruyff Arena in Amsterdam and Zenit Saint Petersburg’s Gazprom Arena have retractable roofs.

There are also roofs at the Merkur Spiel-Arena — of Fortuna Dusseldorf — Denmark’s Parken Stadium, Lille’s Stade Pierre-Mauroy, the Stadion Narodowy in Warsaw, Stockholm’s Tele2 Arena and Deutsche Bank Park in Frankfurt.

The Millennium Stadium, which is primarily used for rugby union, has a retractable roof — more on that in a bit. And there are four tennis stadiums with retractable roofs — Centre Court and No 1 Court at Wimbledon, OWL Arena in Halle, Germany, and Stade Roland Garros.

How does closing a roof impact other grass sports?

The most comparable sport regularly played in a closed-roof stadium is probably the NFL. There are 10 stadiums in that league that either have fixed roofs or retractable ones.

There has always been a sense that indoor stadiums lead to more points being scored. As The Athletic’s Hannah Vanbiber explained in January — before this year’s Super Bowl at the domed Allegiant Stadium in Las Vegas — indoor Super Bowls tend to a bit higher scoring than outdoor ones, with outdoor Super Bowls averaging 44.6 points. But the first 11 Super Bowls were outdoors, and many early Super Bowls were low-scoring.

Using Super Bowl XII, the first indoor Super Bowl, as a starting point, outdoor games have averaged 49.7 points per game since then, which is more than indoor games.

The small sample size and different eras render these stats largely meaningless, but it may fight against the theory that indoor venues are ripe for many points.

There is also the case of Jared Goff, the Detroit Lions quarterback. As of January this year, he had a 69 per cent pass completion rate in indoor venues, with a 64.5 per cent pass completion rate at outdoor venues. Playing indoors had an impact on him.

Since the All England Lawn Tennis Club installed its roof at Wimbledon’s Centre Court, there has been a sense that it has impacted the air in the venue and made the ball move slower.

In 2011, Professor Steve Haake of Sheffield Hallam University’s department of sports engineering said to the Daily Mail: “The roof closes when it rains, and it takes 10 minutes to do so — that means the grass will still be damp.

“This could fluff up the ball, because the balls pick up the moisture from the ground. Even a small increase in its size will make it less aerodynamic and therefore slower. That would be the major factor.

“Changes in temperature and humidity will also affect the flight of the ball.

“The colder the air, the thicker it becomes, and the slower the ball will travel. A drop of 5C (41F) in temperature increases the air density by two per cent.”

He also explained that a lack of breeze also causes an issue with perspiration, as sweat will not evaporate as quickly. This makes players feel like it is more “hot and humid” than it really is. Wimbledon has an “air management” system designed to mitigate this, which is configured to emulate normal grass court tennis as closely as possible. In New York and Melbourne, at the U.S. Open and Australian Open, roof closures have recently protected players not from rain and humidity, but from extreme heat by providing shade over the court.

Is there any controversy around closing roofs at stadiums?

Yes. Going back to the Millennium Stadium, there are always huge issues around closing the stadium roof, especially for the bigger games during the rugby calendar.

There have to be very specific conditions for the roof to be used. For Six Nations games, both sides have to agree on whether they want it closed or not before it can be closed. This can cause off-pitch tension before the match.

There is also a sense that the atmosphere benefits from the roof being closed — which can often be seen as a reason one team will not want the roof to be in use.

For example, this February, Wales head coach Warren Gatland expressed anger at Scotland’s desire to keep the roof open despite rain being forecast, suggesting it was part of a plan to limit the impact of the Welsh crowd. In turn, Scotland head coach Gregor Townsend claimed that the ball can become “greasy” if the roof is closed.

What have sports stars said about playing at stadiums with roofs?

Former England flanker James Haskell admitted that there was a clear impact from closing the roof at the Millennium Stadium when his side played Wales.

He said the atmosphere was much more powerful, and told WalesOnline: “If the roof is closed and you’re 10 metres from the Welsh line, or they’re 10 metres from your line, the noise becomes so oppressive it’s like a force on top of you.”

In tennis, the most notable recent match was the 2023 women’s Wimbledon final between Marketa Vondrousova and Ons Jabeur. The roof was closed pre-match — rather than the usual change of weather necessitating it — due to high winds.

Vondrusova, who won, said: “I was really happy they closed the roof because it’s very different than in the windy weather.

“The roof can help you with serve. You don’t have to focus on the wind so much. I feel like everything is the same on every side. You just have to focus on the game, not on the wind, not even on the sun.”

Most tennis players prefer to use the roof as little as possible, despite the weather, because they are fundamentally meant to be outdoor events.

How do City feel?

City manager Pep Guardiola seemed pretty blase when asked on Monday. He said: “I’m curious to see it. It’s curious because I’ve never seen it at a game — maybe for pre-season in the United States at some point — but in an official game I’ve never seen it and I’m looking forward to it.

“Last year, it was almost finished, is it (finished) now? (Reporter: Yes, it’s finished, it’s going to be played with the closed roof.) It’s good we’re going to see it.”

When asked after the roof closure was confirmed on Tuesday, City said they had no outlook on it.

(Top photo: Thomas Coex/AFP via Getty Images)