The first man to leave was Radamel Falcao. Then Alvaro Negredo departed, then Roberto Soldado. Last season's third, fourth and fifth top scorers, all gone. It is not just them either. Neymar came to Spain, joining Barcelona, and Real Madrid remain confident that Gareth Bale will too. They dominate the agenda – over the past month, 28 of Marca's 30 covers have been dedicated to Real, 10 of them to Bale, with AS mirroring those figures exactly – but the summer has been marked by movement in the other direction, by the exodus. The new season will be too.

A dash through the squads, pen in hand, reveals more than 70 players who have left the Spanish league this summer. Not all of those are a problem, of course. Some went because it suited their clubs in footballing terms; others departed for specific, one-off reasons and it is no great revolution for other players to have headed for big clubs in big leagues. Thiago Alcântara to Bayern Munich and Gonzalo Higuaín to Napoli are deals grounded in a certain logic and facilitate transfers that are bigger yet for Real and Barcelona. But it runs deeper than that and this is a symptom of a serious crisis.

Only six first division clubs here have been net spenders so far this summer: Real and Barcelona, then newly-promoted Villarreal at €6.7m (£5.7m); Granada, propped up by Udinese, at €6.3m; Valladolid at €250,000; and Elche, who have spent €50,000. According to figures in AS, for the second year in a row Spanish clubs have collectively made more on transfers than they have spent. English, French and Italian teams have all spent more in absolute terms than Spanish ones. German, Ukrainian, Russian, Turkish, Portuguese and Dutch clubs have all spent more in net terms.

Players have left Spain for teams in Argentina, Brazil, Greece, Abu Dhabi, Russia, Qatar, Mexico, Denmark, the US, Belgium and Azerbaijan. Their clubs have almost all sold because they have to. Spanish football's collective debt is almost €4bn. More than half the teams in the top two divisions have been through administration. Málaga and Rayo Vallecano were denied a Uefa licence. Spain's clubs owe almost €500m to the Inland Revenue; now, at last, the government is getting serious. It's time to pay back the debt and there is only one way to do that. As the secretary of state for sport puts it: "Players must leave."

The impact on the quality of the league and the title race is obvious, reinforcing a trend that was already apparent. Real finished 2012-13 15 points behind Barcelona, the biggest ever gap between first and second. José Mourinho had publicly conceded the title before Christmas; by their standards, it was a disaster, yet their 85 points is their joint-fourth highest total ever. It's just that Barcelona reached 100, equalling the record set by Real the year before. Seven times a team has gone over 90 points; all seven have happened in the last four seasons. What was it Pep Guardiola called it? Fucking barbaric. No one else could compete.

For a while last season it looked like Atlético Madrid might – and their Copa del Rey victory was one of the great footballing stories, perhaps their best night ever – but ultimately they finished nine points behind Real and 24 behind Barcelona. In terms of points, fourth-placed Real Sociedad were closer to the bottom than the top, just as third-placed Valencia had previously been, three seasons running. Both Atlético and Real Sociedad had enjoyed a superb season, but then the former lost Falcao and the latter lost central midfielder Asier Illaramendi to Real for €38.5m.

That was just the start. Carry on down the table and the pattern is startling. Two teams strengthen, everyone else weakens. In fifth, Valencia lost their best player, Soldado, following David Silva, David Villa, Juan Mata and Jordi Alba out the door. In sixth, Málaga lost Jérémy Toulalan, Joaquín, Júlio Baptista and Isco, who joined Real. And in seventh, Betis lost both central midfielders, including playmaker Beñat. Rayo were eighth: they've lost pretty much everyone, including their top scorer. In ninth, Sevilla sold Jesús Navas and Negredo, their most outstanding players.

On top of that, Athletic Bilbao finally sold Fernando Llorente to Juventus. Of the Spain squad at the Confederations Cup, nine will play abroad this season. Only one will play in Spain at a club other than Madrid or Barcelona – and that's Villa, now 31, who the Catalans let go.

If the rest could not compete last year, how can they compete this year? The answer of course is that they can't. For many that is no longer the point; it is not even about competing any more, it is about surviving. New season, same candidates. Not just to win the league but to win virtually every week: a defeat-free campaign may not be far off; 36 matches, decided by two clásicos? It could yet happen.

For some fans, that's a depressing scenario. Yet the coming season is not a write-off, nor a switch-off, even if knowing when to switch on will be an adventure in itself.

For the big two, winning is not so much an objective as an obligation; draws are the new (or the not-even-so-new-now) defeats. Any points dropped can be decisive and every mistake is magnified. It does not always feel like it, but that constant tightrope walk gives a tension and edge to their every game, piling pressure on the players, even if it will be Europe that truly defines their seasons. And then there's, simply, the quality of their football, the talent of their players. Leo Messi, Cristiano Ronaldo, Neymar, Isco, Andrés Iniesta, Mesut Özil … Bale? It's hard not to be just a little excited.

Domestically, the advantage may be Real's. There are positive signs with Tata Martino, with the recovery of high pressure vital. But Barcelona's pre-season was preceded by the impact of Tito Vilanova's illness and Thiago's departure and has been largely a mess, with bad pitches, bad planes, bad preparation and even bad food. Meanwhile, Real's has been impressive. Barcelona are yet to sign a central defender and although Madrid too could find themselves short at the back and the No9 position, a kind of galácticism creeping back into their planning, there is a palpable sense of relief about the place, a release. Isco, in particular, has impressed.

In the opening weeks of the season when there may still be a touch of vulnerability, in those weeks where Madrid lost the title last year, the fixture list probably favours Carlo Ancelotti's side too. Barcelona face Málaga, Valencia, Sevilla and Real Sociedad in the first six weeks; Madrid face none of them. Perhaps their only theoretically difficult fixture is Athletic in week three.

Besides, although it is all about them, it is not just them. And it is striking how optimistic some supporters are, now that they have let go of the title itself. Good players remain; better ones will emerge. The scouting, coaching and preparation remains excellent, the talent doesn't dry up. Spain keeps producing footballers. Crisis is opportunity and there will be much worth watching. Villarreal back up and with Giovani dos Santos, Celta under Luís Enrique, and Granada under Lucas Alcaraz. Elche back in the first division after almost 30 years. Pepe Mel's Betis: 12 players out, 13 players in, but always entertaining. Any team Paco Jémez puts out and any jacket Paco Jémez puts on.

Valencia keep losing players season after season, but running through their squad there's strength there – and, yes, that does include the new signing Hélder Postiga – and there is an optimism and determination about the new coach Miroslav Djukic that is contagious. Real Sociedad may be stretched by the Champions League, assuming they get past Olympique Lyon, but they can probably assimilate the loss of Asier Illarramendi, with Rubén Pardo likely to play more often. And Sevilla have reinvested. There's something exciting about what they're constructing, a team that could compete for a Champions League place: Marko Marin, Ivan Rakitic, Kévin Gameiro, Vitolo … there's not too much wrong with that.

Atlético have lost Falcao, but Villa, if he is fully fit, and Leo Baptistao feels like a reasonable and bright swap, with the potential to be genuinely thrilling, especially alongside Arda Turan, Diego Costa and Oliver Torres. Just ask the 20,000 who turned up for Villa's presentation, or those who saw his first goal for the club screech into the top corner. Torres, meanwhile, is a very, very special talent.

Then there's Athletic Bilbao: Llorente departed physically this summer, but departed mentally last summer, spending a year in limbo, rejected by fans and club. His actual leaving is a relief not a problem, particularly with Aritz Aduriz in the side. Beñat and Kike Sola have joined, while others will surely be recoverable now that Marcelo Bielsa has gone, replaced by the excellent Ernesto Valverde. Get Iker Muniaín fit and focused and a Champions League challenge may not be beyond them as they embark on their first season in a century away (but not far away) from San Mamés.

With Atlético, Athletic Bilbao are arguably the only side that have actually improved in a division when even standing still is an advantage. For the rest, there may be some consolation in convincing themselves that the step back might not be as bad as it looks, especially when everyone else has taken a step back too. Everyone, that is, except Real and Barcelona, but then they long since disappeared into the distance. And no one is even trying to chase them any more.