The former head of global track and field, Lamine Diack, again said he was surprised by the behaviour of his absent son as their corruption trial resumed in Paris on Monday.
Diack, who headed the International Association of Athletics Federations (IAAF) from 1999 to 2015, and his son, Papa Massata Diack, are among those accused in relation to bribes paid to cover up positive dope tests by Russian athletes.
Papa Massata Diack remains in Senegal which has not agreed to extradite him to France.
On Thursday, Lamine Diack told the court he had been "flabbergasted" to learn from prosecutors that his son had got involved in the doping cases.
On Monday, he said he was surprised to discover how much commission his son was taking on sponsorship deals he negotiated on behalf of the IAAF.
Lamine Diack said he did not know that VTB, a state-owned Russian bank, paid 29 million euros ($32.75 million) to sponsor the IAAF from 2007 to 2011, while his federation only received 19 million euros.
The remaining 10 million euros ended up in the account of a company called "PMD", the son's initials.
One of the charges against the Diacks is that, in return for covering up doping cases, they received help from the Russian authorities in renewing sponsorship and broadcasting contracts with VTB and Russian television channel RTR, as well as funds to finance political campaigns in Senegal.
Lamine Diack is also accused of allowing his son to appropriate millions from not only the VTB deal, but from Korean electronics company Samsung and Chinese broadcaster CCTV.
Lamine Diack told the court he was unaware that the IAAF marketing rights were being sold to the Japanese advertising giant Dentsu, which in turn allowed the son's companies to act as intermediaries.
The son profited from those deals and also by taking "exorbitant" commissions of around 20 per cent on top of his daily salary as IAAF marketing consultant of $900 dollars rising to $1,200 when he was working.
'I DON'T UNDERSTAND'
Asked by the presiding judge in the trial, Rose-Marie Hunault, if he had a problem with his son wearing two hats, Lamine Diack answered: "I thought he could sell."
In an interview with L'Equipe in 2016, Papa Massata Diack boasted that he was responsible for $678 million out of a total of $925 million in IAAF marketing rights.
Asked to explain the transfer of 600,000 euros to his bank account by his son between 2011 and 2015, Lamine Diack said on Monday that he had no precise recollection.
The 87-year-old Diack often gave confused and fragmented answers, punctuated by "sorry?", "I don't understand", "I don't know".
Asked by his lawyer whether his fourth term as IAAF president had been one too many, Lamine Diack whispered "unquestionably".
The examining magistrates deplored Senegal's "total lack of cooperation" in the case.
Lamine Diack has said the Russian money helped finance Macky Sall's successful campaign to unseat Abdoulaye Wade as national president in 2012.
Senegal gave Papa Massata Diack a diplomatic passport in 2014.
The trial ends on Thursday.