Representatives of at least two clubs in the leading divisions of English football are said to have paid for information relating to the selection and tactics of rival teams.

Marcelo Bielsa’s admission that he sent someone to spy on Derby County training last week has led to a complaint that is now being investigated by the Football Association and Football League.

The controversy further escalated on Wednesday when Bielsa called a press conference in which he admitted to having had all of his opponents’ training sessions watched.

One source connected to a leading Premier League club, however, told The Telegraph it was known inside football that representatives of at least two prominent clubs are ready to pay for informed team news. That might be to an employee of a rival club, an agent, a player or even a relative of a player.

Watching opposition training sessions wherever possible, and gathering intelligence through a network of contacts, was also said to be standard. According to the source, the general attitude is that it is for each club to maintain privacy over training sessions and ensure that they employ people who do not give out team news.