When Michu turns up at the Emirates Stadium with his Swansea City team-mates this weekend he will seek out Arsenal's playmaker Santi Cazorla, give him a hug and talk. They will talk about life in a new country and life back in the old country. Conversation will no doubt turn, as it has done often since the start of November, to the club where they started their career and the momentous month it has just been through, a club that has been reborn thanks not least to them.

Michu, Cazorla and Chelsea's Juan Mata all began their careers with Real Oviedo in Asturias, northern Spain. Right now there may be no club in the Premier League that can lay claim to having discovered and developed three current players of that level. "Oviedo taught Santi and Mata to play," says Michu – all of which may not seem that remarkable but for one thing: Oviedo are not a first division side and have not been for a decade. It is 10 years since they even played in the second division and they currently play in Spain's second division B, a third tier made up of four divisions of 20 teams each.

It is a territory Michu knows well; he has been there with them. He was with them this month, too, as they faced an even worse fate: at the start of this month Oviedo were on the verge of disappearing forever, their president seeking legal advice as to how to carry out a liquidation. One current Oviedo player says Michu has been on the phone constantly: "What's happening? Are we going to make it?" The answer, in the end, was: "Yes, thanks to you." That a historic club survived owes much to the three Premier League players and the Premier League's reach.

Michu, Cazorla and Mata all put their hands in their pockets and carried the torch. A month later the outlook could not be more different. Oviedo have more shareholders than any other club in Spain and one of them is the richest man in the world. Now, say the new owners, it is time to take Oviedo back to where they belong – the first division.

They have not been there since 2001, when they were relegated at Mallorca on the final day. Their financial problems had begun and there were political battles too: the club's president and the city's mayor represented opposite sides of the political spectrum.

Another relegation followed the next summer when players formally denounced the club to the players' union for non-payment to go with on-pitch failure. And the year after that the local government withdrew support for the club and put its weight behind third-division Astur instead. "All that is left," said one board member at the time, "is to sign the death warrant."

It went without signing. Juan Ramón González formed part of the supporters' association, now he is on the board at Oviedo. He has been the key figure at the club over the last three weeks. Looking back on 2003, he is fond of quoting a line from the Spanish version of Neil Young's Like a Hurricane: "The poison saved you".

Subsidies were poured into Astur, their kit was changed to blue and white, like Oviedo, the badge was altered and they even changed their name to Oviedo AFC. The man who had played more games for Oviedo than anyone else, Berto, was signed up and plans were made to take Oviedo's municipally-owned Carlos Tartiere stadium away. But instead of killing the club, it was a reawakening.

The "Real" in Oviedo's name took on greater significance than ever. Oviedo fans rebelled, mobilising to save their club, protesting, raising money, forcing the local government's hand. They called it Espíritu 2003 – the spirit of 2003. The council backtracked, but the club's situation remained far from ideal: playing on what were little better than park pitches, thousands turning up to see them in arenas not even built to house hundreds.

Since relegation from the top flight Oviedo have never gone under 10,000 season-ticket holders. Right now, only two teams in the second division A, let alone the second division B or the 17-division third division, can claim as many. Amid the uncertainty, in 2003, Oviedo lost Cazorla and Mata to Villarreal and Real Madrid respectively; Cazorla was 17, Mata was 15. This summer they won the European Championship together; between them they have raised almost €50m (£40.5m) in transfer fees. But they did look back. Every summer they return and they have remained members.

Michu's path to the Premier League was different. He made his debut in the third division at 17 and spent four seasons at Oviedo; the club's current idol, the striker Diego Cervero, is among his best friends. Together they won promotion from the third division to the second B in front of 25,000 fans.

Michu has lived Oviedo's darkest hours, later joining second division Celta. He turned down the opportunity to play first division football because the club that offered him the chance were Sporting Gijón, Oviedo's rivals. Eventually he got another opportunity at Rayo Vallecano. Fifteen goals and he became one of the Premier League's bargains of the season.

It is notoriously hard to escape the second division B, where four divisions funnel into one and an almost perfect season can be destroyed by one bad game in the play-offs, and Oviedo did not escape. Their problems were getting worse. There was another false dawn, another false idol. In 2006 Alberto González took a controlling share in the club. He paid €200,000 for a team bus that was too big to park in most of the grounds where Oviedo played. He did not pay social security or tax to the inland revenue, then disappeared. He is wanted on two counts of fraud with an international warrant taken out for his arrest, and is believed to be in Cuba or Panamá.

And that was where the board came in and the fans mobilised once more. With González's shares frozen, a new five-man board of Toni Fidalgo, Pedro Zuazua, Juan Ramón Torla, Sabino López and Jorge Sanchez took over in the summer, with the backing of the second and third biggest shareholders. Supporters were represented at last, their voice heard. One of the two shareholders represented was the local council under a new mayor, an Oviedo fan called Agustín Iglesias Caunedo, who had been working for a solution.

But still the club were on the verge of going out of business. They needed €1.9m immediately to avoid a winding-up order, €2.5m to make it to the end of the season and €4m to secure the club's medium-term future. The plan was a share issue, at €10.75 per share. Not only might that have served to raise the cash the club desperately needed, it would also definitively dilute González's stake.

But would they really make it? Privately they feared not but it was the last throw of the dice. The response was gigantic, unexpected. Cazorla, Michu and Mata were fundamental in giving the campaign international projection. They, like Atlético Madrid striker Adrián, who made his debut for Oviedo at 17, the year after Michu did, all promoted the drive to buy shares and they bought shares themselves. Club sources describe the amounts as "significant".

Momentum built; the campaign grew. Real Madrid bought €100,000 worth of shares, which they ceded to the local council. A Save Real Oviedo banner appeared in the stands during Celtic-Barcelona, World Cup winners anonymously bought shares and on the Sunday afternoon, midway through the process, more people went to watch Oviedo at the Tartiere than watched Barcelona at Mallorca.

Their opponents were Real Madrid C; their players, too, bought shares. Across the front of the stand a huge banner was directed at supporters round the world who had bought shares: Thanks, grazie, gracias, merci, efharisto, it ran.

The response from Oviedo fans was even greater. "The fans are the best thing about the club," Michu told the Sun. "They never cease to amaze me." The spirit of 2003 was rekindled. The example had been set in the summer when one morning fans turned up at the training ground armed with detergent, brooms and cans of paint. Once the training ground was repaired their next stop was the stadium. No one on the board got much sleep for weeks and they fought to make the most of every gesture, every opportunity. A PayPal account was set up in a matter of hours.

In two weeks €1.93m worth of shares were bought by more than 20,000 people in more than 60 countries. Small shareholders alone had rescued the club in the short term; long-term viability was secured too. If anything could convince investors that Oviedo was worth the effort, this could. At the same time as all that was going on, the journalists Paco González and Marcos López hatched a plan via the radio show Tiempo de Juego. They called Arturo Elías, son-in-law of the Mexican telecommunications magnate Carlos Slim, and joked that he should come and save the club.

Many a true word said in jest. Behind the scenes López kept up the pressure, brought Elías into contact with Oviedo's president, Toni Fidalgo, and silently, skilfully saw through negotiations. On the final day of the share issue Slim bought €2m worth of shares; further investment is anticipated but the message is a cautious one.

From the verge of extinction Oviedo had now attracted the world's richest man. Celso González holds 4.16%, the council holds 8.4%, and Alberto González, still in hiding, has seen control wrested from his hands with his holding dropping to 12.41%. Carlos Slim's Carso holds 32.44%. But he is not the majority shareholder, the fans are: 40.81% of the club is owned by small shareholders and Oviedistas. This weekend two of them will meet in north London and celebrate a new beginning.