The former head of world football Sepp Blatter was on Monday attending a hearing in Switzerland as part of a fraud case.
Swiss prosecutors are investigating Mr Blatter, 85, over a payment of $2.2 million made in 2011 to former Uefa president Michel Platini.
The hearing had been postponed until this month due to the retired Swiss football president's poor health.
"This morning, Mr Blatter went for his hearing at the federal prosecutor's office in Zurich," his spokesman Thomas Renggli said.
"Mr Blatter is happy. He said it has gone well so far and he hopes the hearing ends tomorrow."
Mr Blatter said he would return on Tuesday to resume the final hearing in the investigation.
"It is a normal audience. It's the first part. The second part will be tomorrow," he said after the hearing. "It was in a good spirit."
In March, Mr Blatter was convalescing in a clinic after spending December and January in hospital.
Because of his condition, the hearing with a federal prosecutor from the Office of the Attorney General of Switzerland was expected to last for only 90 minutes.
Mr Blatter became Fifa's general secretary in 1981 and the president of world football's governing body in 1998.
He was forced to stand down in 2015 and was banned by Fifa for eight years, later reduced to six, for authorising what prosecutors called a "disloyal payment" to the former French football star Mr Platini.
The ban was imposed for multiple breaches of Fifa's ethics code and Mr Blatter was fined one million Swiss francs ($1.1m).
"The criminal proceedings against Mr Blatter are now being conducted on suspicion of fraud, breach of trust and unfaithful business management," the OAG said before the hearing.
The investigation, which was set up in 2015, is examining the payment Mr Platini received from Fifa for an advisory job completed in 2002, on suspicion of "complicity in unfair management, embezzlement and forgery".
Mr Blatter insists the payment was legitimate.
"It was based on an oral contract that regulated Mr Platini's advisory activities for Fifa between 1998 and 2002," he said. "The process was correctly declared as a late payment of wages."
Prosecutors said they could not put a timetable on concluding the investigation.