Thirteen footballers have tested positive for social drugs since 2012 but their identities were kept secret by the Football Association.

The governing body guard the privacy of players who fail tests for recreational drugs like cocaine and ecstasy on non-match days, arguing it helps support their rehabilitation.

Sportsmail revealed last week that Stoke's new striker Saido Berahino tested positive for a social drug in September when at West Bromwich Albion and served an eight-week ban. Albion fans were told at the time the 23-year-old had been left out of the team to work on his fitness.

Saido Berahino played against former club West Brom after revelations of his failed drugs test

The FA are one of the few governing bodies to test players for recreational drugs out of competition and hope to conduct almost 5,000 tests a season by 2018.

Football already conducts more tests than any other sport in England. UK Anti-Doping testers working on behalf of the FA took 2,442 samples last season and the quantity is expected to top 3,000 this season.

The players caught taking social drugs between July 2012 and June 2016 represent a tiny number (0.17 per cent of all samples) but will surprise supporters who may have been given other reasons for players' absences.

West Brom fans believed Berahino was missing from first-team action earlier this season because of fitness issues but he was in fact banned after testing positive for a recreational drug at the training ground. Prior to Berahino's case, there were 13 positive tests in the four seasons up to the start of this campaign.

Figures show the Stoke striker, who served an eight-week ban earlier this season, is far from alone in having served a drugs suspension in secret

Former Sheffield United midfielder Jose Baxter is understood to account for two of those, and goalkeeper Aaron McCarey was named by his club, Wolves, in May 2015. McCarey is now at Ross County. The identities of the rest remain secret.

There were three positives in 2015-16, six in 2014-15, three in 2013-14 and one in 2012-13.

'Football, rugby and cricket are focusing on the illicit recreational drugs outside of competition and then applying misconduct penalties because it's not really a doping offence,' said UK Sport's former anti-doping chief Michele Verroken when discussing two unnamed Premiership rugby players testing positive for cocaine last month. 'They want players to come forward and seek help, go through clinical assessment and rehabilitation.'

Jose Baxter (right) is understood to account for two of the positive tests while Wolves keeper Aaron McCarey - currently on loan at Ross County - was named as another

The FA's programme goes further than domestic governing bodies in cycling, tennis and athletics in testing for substances such as cocaine and ecstasy out of competition.

Players and clubs must submit their whereabouts to a database so random tests can be carried out on any given day — either at training grounds or home addresses.

Failure to report movements correctly results in a strike and three strikes lead to a charge, as happened to Manchester City and Fleetwood Town last month.