As the National Crime Agency studies footage of Sam Sodje punching an opponent in the groin twice before being sent off in a League One game last season, conventional wisdom still says there is a safe distance between spot-fixing in the lower divisions and match-fixing in the Premier League.

It's a problem; but it's not a big-league problem. That opinion went unchallenged in Spain until April.

With five matches left to play in La Liga, mid-table Levante, with nothing to play for, entertained Deportivo La Coruna, in desperate need of points to avoid relegation.

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Levante were 3-0 down at half-time and in the dressing room during the break, midfielder Jose Barkero accused some of his team-mates of deliberately not trying. He pointed the finger at goalkeeper Gustavo Munua and defenders Sergio Ballesteros, Juanlu and Juanfran in a heated exchange that ended with flying energy drink bottles and Barkero being calmed down by then Levante coach Juan Ignacio Martinez.

Levante lost the game 4-0 and the following day Barkero apologised to his team-mates for the accusation and subsequently gave a press conference in which he said he regretted suggesting that they had deliberately lost the match.

Ballesteros, the captain, also gave a press conference and claimed he would never take payment to throw a result. He also said he never placed bets on matches. The players at the centre of the storm played very little part in what was left of Levante's season and all but one moved on in the summer.

The Spanish Football League appeared to dismiss the retraction of the original accusation and its recently installed new president, Javier Tebas, admitted the match had been under investigation before it was even played. The game is understood to be one of several matches from last season still being looked at. It was a wake-up call.

For years Spanish football had turned a blind eye to the tradition of maletines – briefcases full of money paid from one team to another before matches played towards the end of the season. The reasoning usually goes: team A has nothing to play for; team B is fighting to stay up or win promotion; so team B pays team A to win a game against team C – one of team B's main rivals. It was paying a side to try harder rather than paying them to throw a match so what was the problem?

But the globalisation of the betting industry means the potential for financial inducement now goes far beyond the briefcase handed over at the motorway service station. Spain made match-fixing a criminal offence in 2010 as a response to changing times and at the start of this season the league hired FederBet, an online tracking agency with the resources to detect suspicious betting patterns.

Last week, FederBet published its first European report on this season and of 51 games around which the company had detected unusual betting patterns, there were two from Spanish football.

A win for Real Sociedad over Granada last month in the women's First Division aroused suspicion primarily because a single bet of €50,000 (£42,000) had been placed on it – when such a match would normally attract bets of €200,000 (£168,000) in total. A 1-1 Second Division draw between Constancia and Gimnastic Tarragona also raised suspicion.

The big bet on the women's game was for Real to beat Granada by more than one goal. It finished 3-0 to Real and, according to match reports, one goal came from a controversial penalty and another was scored from an offside position.

FederBet's ability to inform the league immediately of suspicious betting patterns is part of a dual approach employed by Tebas. The league also insisted at the start of the season on there being a players' delegate inside every dressing room who team-mates can go to in the event of being approached to spot-fix or match-fix. The squad representative would then report the incident.

"Everyone knew Spain was not the convent of Europe" said Tebas at the start of this season. "Betting mafias need to know that we are not going to be fertile ground for such activity," added his assistant, Ricardo Resta.

FederBet's involvement serves as a deterrent. Director Francesco Baranca said: "Most clubs don't want to hear negative findings but we don't accuse teams of wrong-doing, we just report on the betting movements. The club itself could be the victim."

The fact that their first findings this season implicate the women's game and the third tier of the men's game might reinforce the idea that this is not a top-flight problem. But memories of events surrounding Levante 0 Deportivo 4 last April mean there is no room for complacency.

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