THG Sports executive Kevin Mallon refused to answer police questions in Rio yesterday
Pat Hickey is due to speak with police in Rio later today.
Mr Hickey, the former president of the Olympic Council of Ireland (OCI), is one of two Irish men being investigated in connection with alleged ticket touting at the Olympics.
The other man - Kevin Mallon, an executive with the ticket firm THG Sports - refused to answer police questions in Rio yesterday.
Both men have denied any wrongdoing.
Reporter Matt Sandy in Rio says police spoke to journalists about the case involving Kevin Mallon yesterday.
"[Police] revealed that something in their investigations so far led them to want to re-question Mallon, and hoped to get more information out of him," he explained on Newstalk Breakfast. "But obviously that didn't happen."