Ireland's President Michael D. Higgins.RollingNews.ie

Irish President Michael D. Higgins has warned that serious doping and administration issues surrounding Ireland’s part in the Rio 2016 Olympic Games could undermine public confidence in sports.

He was speaking at a reception for some of the athletes who returned to Ireland from Rio, and as the Olympics Council of Ireland’s resigned President Pat Hickey prepared for release from jail to continue being held under house arrest in Brazil.

The Aras an Uachtarain reception was held against a background of investigation by Brazilian police into alleged Irish ticket touting in Rio.

There was also a background of one Irish boxer being sent home after being tested positive for a banned substance, two Irish boxers being investigated for gambling (not illegal but banned by the International Olympics Committee), and controversial boxing decisions after which some referees and judges were removed from the panel.

Higgins admitted there were “serious issues” surrounding Ireland’s involvement in the Olympics, but that they should not overlook the achievements of the athletes involved.

“Each of these issues, if not adequately addressed, has the potential to undermine public confidence in our athletes, in our sporting administration and in the fairness of international sporting competition itself.”

Meanwhile, German newspaper Süddeutsche Zeitung reported the discovery of emails showing Hickey demanded hundreds of extra tickets for prestige events at the Rio Games from the head of the International Olympic Committee. The newspaper claimed to have seen emails from Hickey to Thomas Bach, president of the IOC.

Imprisioned over ticket touting scandal, Patrick Hickey.

Imprisioned over ticket touting scandal, Patrick Hickey.

The emails do not show whether the extra tickets were given to the Olympic Council of Ireland.

A judge agreed on Monday to allow Hickey – who has stood down temporarily from all his Olympic roles - to be kept under house arrest while a file is prepared for his criminal case.

The 71-year-old faces charges of forming a cartel, facilitating ticket touting and ambush or illicit marketing, an offense created especially to combat touting in Brazil.

Kevin Mallon, Hickey’s cellmate in Bangu Prison and a director at ticket agency THG, was released on bail on Sunday and also placed under house arrest.

Both men, two ticket agencies and the Olympics Council of Ireland, have denied any wrongdoing.