Here we go again: Saturday night at the Santiago Bernabéu, the title decider. Eighty-five thousand tickets long gone, history there to be made. First versus second, 100 goals between them, the rest way behind. The club that are unbeaten at home, with more points than anyone in Europe, hosting the club that have not lost away, the league leadership awaiting the winners. Top scorers face to face, battling for the Pichichi. That symbol of Spain against the side supported by the Catalan president in exile. A banner the size of a building suddenly appearing in the capital: we’re coming for you. It’s all set up to be a classic, but it’s not a clásico.

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This isn’t Real Madrid against Barcelona; it’s Real Madrid against Girona. Somehow, Girona made it this far; win on Saturday and Míchel Sánchez’s side may believe they really could make it all the way. They beat Barcelona and they beat Atlético Madrid; beat Madrid and it’s real. The club that have never won anything, never even reached Europe, that only got to the first division in 2017, went back down again, and are playing only their fourth top-flight season, whose budget is a 14th the size of Madrid’s, could actually win the league.

“We want to make history at the end of the season,” Míchel said. “Departing the Bernabéu top would be special too, it would leave Girona on everybody’s lips. But we still wouldn’t be candidates to win the league. There are still 14 games left and I think Madrid and Barcelona will win lots of games. For us, every game is difficult. To win the league, you need 85-90 points and we have 56. Madrid can do that, so can Barcelona, and Atlético have done it. It’s not fair for anyone to demand we win the league.”

There is no demand, although there would be disappointment if they fall away, which says something about what they have done, the impossible looking more possible by the week. Girona are not supposed to be up there but here they are and they have stubbornly refused to let go. They come into this trip to the Bernabéu having been top of the table in nine of the 23 weeks so far, moving into first place four times. Only two points behind, that will extend to a fifth, if they win, making it 10 weeks in total. So far. No wonder the L word has been used increasingly frequently: Leicester.

Can Girona do what Leicester did? On the evidence until now, they can. In fact, having collected 56 points after 23 games and losing only once, they are outperforming Claudio Ranieri’s side, who finished 2015-16 on 81 points, having lost three times.

The problem, as Míchel suggested, is likely to be the other teams. In 2016 Arsenal finished second on 71, having been beaten seven times. Spurs were third on 70. Madrid are already on 58 with 45 to play for.

“Whoever wins tomorrow will have an advantage, but this [season] is very long,” Carlo Ancelotti said on Friday. “Girona come with big hope, motivation. They could win the game and lead the league and we have to keep that in mind. But tomorrow doesn’t decide anything: the league will be decided later, whatever happens.”

Whatever happens, this has been an extraordinary season, reflected in the fact that anyone dares suggest that this is the title decider. This week, a huge banner was erected in central Madrid, carrying echoes of the Barcelona president Joan Laporta’s election campaign. Organised by an HR company that is one of Girona’s sponsors it shows their players celebrating with the slogan: “When your CV isn’t everything.”

Girona have the smallest stadium in the first division, at 13,942, in a city that is far from football mad, and where many people support Barcelona, 99km away. This is a club with no major trophies – they have one Catalan Super Cup, plus titles in Spain’s third and fourth tiers but no more – and a squad with very few too, Daley Blind alone responsible for more than half of them. Look at the CVs of Girona’s players and what they do have is 37 relegations between them.

The announcement that the Brazilian winger Sávio, on loan from Troyes, will be joining Manchester City underlined the flaw in the fairytale. Troyes and Girona are owned by the City Football Group. Forty-seven per cent of Girona belongs to City; Pep Guardiola’s brother Pere owns 16%. “They have the money to rent a space [for their banner] in Madrid, and that can’t be cheap,” Ancelotti noted.

Real Madrid's Santiago Bernabéu stadium [pictured] will stage a regular-season NFL game in 2025, it has been announced.

The fixture, between two teams yet to be named, will be the first NFL game to be held in Spain, adding Madrid to a list of European hosts including London, Munich and Frankfurt.

NFL commissioner Roger Goodell said: "Playing a game in Madrid in 2025 highlights the continued expansion of the league's global footprint and the accelerated ambitions to take our game to more fans around the world."

Reports in Spain say that either the Miami Dolphins or the Chicago Bears, both of whom have international marketing rights in the country, will play host to the Madrid fixture.

São Paolo will stage a game in 2024 at the Corinthians Arena, with the Philadelphia Eagles the designated home team. It will be the first NFL match played in South America; Mexico City and Toronto have also hosted games outside the US in recent years. PA Media

And yet that alone doesn’t explain nor entirely diminish what Girona have done on the pitch: only two players belong to the City Group, their salary limit is set at €51m (£43.5m) compared with €727m for Madrid, and the most expensive player in their history is Artem Dovbyk, who cost €7m for 50% of his registration. Dovbyk is La Liga’s joint-top scorer on 14 with Jude Bellingham, who cost €103m.

This is still a group of players, and a coach, who weren’t supposed to be anywhere near here. They haven’t gone down the traditional defensive underdog route either, still less done it the dirty way. They put four past Atlético, four past Barcelona and have scored more than anyone. There have been three 4-2s, a 4-3, a 5-2 and a 5-3. Fourteen players have found the net. No one in the league has completed more dribbles or provided more assists than Sávio. Only Kirian Rodríguez has completed more passes than Aleix García. Their only defeat was against Madrid, and even then their shot count was in double figures.

That night Girona lost the top spot that they had claimed for the first time in their history. And that, everyone assumed, was that. “We can’t compete as equals with Madrid,” Míchel said, but here they are standing before the chance to take it back again. “We’re in a fight we didn’t expect,” admitted the club’s president, Delfí Geli. Saturday night at the Santiago Bernabéu, the league on the line.