Invest in soccer? Check out the safest clubs

Olivier Giroud of Arsenal jumps to head the ball during the Barclays Premier League match between Fulham and Arsenal at Craven Cottage on August 24, 2013 in London.
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This year's World Cup has boosted soccer's global appeal, with teams and players becoming household names across the world – and investors are also getting in on the "beautiful game".

The stock market listings of iconic clubs such as the U.K.'s Manchester United and Italy's Juventus mean the investment opportunity is there, but how do you know if you're backing a winning team?

S&P Capital IQ has devised a way to help investors keep on top of the game with a "Credit Football League" table, which lays out the credit scores of 44 publicly-listed and private clubs. Its proprietary analysis model takes into account public clubs' stock price movements, performance on the pitch and finances.

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Pitch performance key

Dutch team Ajax topped the league, with Britain's Arsenal, Celtic and Manchester United following close behind. The research suggested these clubs have been consistent in their match performance - a key element of a team's financial success.

Arsenal have won very few championships in recent times, but have qualified for the lucrative Champions League for 18 seasons in a row. S&P's report said that frugal spending on players by the club's manager Arsene Wenger has given the club strong financials and a good credit score.

Some 20 years of success for Manchester United under former manager Alex Ferguson put it in the top five, despite recent struggles which saw it finish seventh in the last English Premier League season and miss out on Champions League qualification.

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French club Racing Club de Lens was ranked bottom of S&P's list of 44, however, with poor ratings for operation, solvency and liquidity.

Euro zone clubs at bottom

There is a divide between teams in northern and southern Europe, according to S&P's league table, reflecting the economic situation on the continent. Of the top 10 teams, 4 are U.K. teams, 3 are German, 2 are French and 1 is Dutch. Towards the bottom of the ranking are clubs from Italy, France and Portugal.

"If you look at the table it seems like there is a north-south divide because the countries harder hit by the recession are where consumer sentiment was a lot lower and people spent less on merchandise and tickets," Pavle Sabic, director of credit market development at S&P Capital IQ, told CNBC by phone.

Clubs in the troubled euro zone also appear at the most risk of default in the short-term, according to analysis of the 17 publicly-listed clubs on S&P's list, which takes into account equity prices. Portuguese team Benfica has the highest "market signal probability of default" at 41.7 percent, compared to the 2.5 percent median. Italy's Roma and Portugal's Porto are also towards the bottom of this table.

S&P did not give any of the publicly-listed clubs an "investment grade" credit score, with Arsenal's bb+ the highest in Europe.

More investor appetite?

The vast quantities of money in the soccer world is attracting international investors from around the world. Deputy Prime Minister of the United Arab Emirates, Sheikh Mansour, took full control of Manchester City in 2009, and Russian businessman Dmitry Yevgenyevich Rybolovlev bought a controlling stake in Monaco in 2011.

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With the continued internationalization of the sport and increasing popularity in the U.S. with Major League Soccer, more investors could look to clubs as attractive places to park their money.

"If we look at where the market has been, 10 years ago we didn't have any public-listed clubs and now we have 17," Sabic said. "It is important to look at financials, because unlike before we are treating these teams as corporations and you have to look at them as such."

- By CNBC's Arjun Kharpal