Leeds manager Marcelo Bielsa has admitted to watching all of his opponents' training sessions before their matches this season in a remarkable hour-long news conference in which the enigmatic Argentine coach disclosed the extent of his research and planning.

Bielsa is being investigated by English soccer authorities for sending a member of his club's staff to spy on Derby County in its training session ahead of a match against Leeds in the second-tier League Championship last week.

Reiterating a previous assertion that he has done nothing "illegal," Bielsa said Wednesday that "I observed all the rivals we played against — we watched all the training sessions before we played them."

Bielsa said that by saying this "I assume the possible sanctions by the authorities."

In a PowerPoint presentation at Leeds' training ground, Bielsa showed journalists his detailed reports and analysis on each of his team's opponents this season, including information on tactics, formations and specific players.

He used as an example the research he did before the Derby game, showing which Derby players had been used in which positions and the formations Derby had struggled against.

Bielsa said he was "ashamed" to have to reveal the information. He said the research carried out by 20 members of staff was "absolutely not necessary" but that "we feel guilty if we don't work enough and we feel it gets us closer to a win even if it's not true."

The English Football League, which governs the three divisions below the Premier League, launched an investigation into the incident on Tuesday, saying Leeds' "alleged actions appear to contravene the club's charter" that all of its teams agreed to before the season.

Leeds tops the Championship standings by four points.