Fifa's technical report of the 2018 and 2022 World Cup bids may have been compromised by the head of the inspection team putting pressure on one of the bidding countries by asking for personal favours, according to the ethics committee investigation.

Harold Mayne-Nicholls, the former Chile FA president who led the inspection team, asked for places for his son and nephew at the Aspire academy in Qatar plus tennis coaching opportunities for his brother-in-law, according to investigators.

Mayne-Nicholls, who has had proceedings opened against him by Fifa's ethics committee, announced in October he is considering standing against Sepp Blatter for the Fifa presidency.

Cases have also been opened by chief investigator Michael Garcia against three serving Fifa executive members — Angel Villar Llona from Spain, Belgium's Michel D'Hooghe and Worawi Makudi from Thailand — and former member Franz Beckenbauer from Germany.

In Mayne-Nicholl's case, an email sent to him from ethics committee deputy chairman Cornel Borbely on November 12th states the Chilean had contacted "a person associated with a bid team" — Andreas Bleicher, Aspire's executive director of international affairs — "shortly after the inspection tour and prior to the issuance of the Evaluation Report on Qatar".

The email, which has been reproduced on the website www.transparencyinsport.org, states Mayne-Nicholls “repeatedly asked for personal favours — including special treatment for family members -, exerting pressure until Mr Bleicher signalled his unwillingness to commit to anything in the near future.”

It adds: “Furthermore, said behaviour seems to be a cause enough to doubt the integrity of the inspection process and your evaluations.”

The evaluation report gave Qatar the worst ranking, mainly due to the extreme heat of the summer, but the country still won the vote for 2022. The country with the second-worst ranking, Russia, won the vote for 2018.

The email from Borbely also asks Mayne-Nicholls for answers to 36 questions, and reproduces email exchanges between the Chilean and Bleicher. It shows in September 2010, Mayne-Nicholls contacted Bleicher asking for places at the academy for family members. Bleicher replied initially that it “would be an honor for us to host your son and your nephew for a football evaluation and training period in Aspire” but later that month responded to a follow-up email saying “considering Fifa’s ongoing bidding process for the Fifa World Cups 2018/2022 with the involvement of Qatar 2022, we believe it might be advisable not to follow up on these topics at this point, as this might leave space for incorrect interpretations, even though Aspire is not involved in the bidding process, of course not.”

Mayne-Nicholls said last month he did not think the ethics case was connected to his announcement that he might run for president.

He said then: “I do not think it is because I might want to run. I think it is because the ethics committee needs to have a very clear picture about everything that happened in the 2018 and 2022 bids. I get relaxed with this because if they are investigating such a small thing then I can imagine how they are investigating the real, big things and that will give us transparency.”

Fifa’s executive committee will be asked to formally vote this week on whether the Garcia report into World Cup bidding should be published.