Barry McGuigan received more than 20% of the £2.4m paid out following a pay per view Carl Frampton title fight, the High Court was told on Tuesday..
Mr McGuigan, on the stand for a third day, was questioned over payments from the February 2016 bout with Scott Quigg, which Mr Frampton won to claim both the WBA and IBF super bantamweight belts.
Gavin Millar QC, for Mr Frampton, asked Mr McGuigan why his client was not paid until 10 months after the bout and about tens of thousands of pounds in expenses for which it is alleged no documentation was provided.
"It would have been discussed with him," Mr McGuigan told the court, which also heard the defendant agreeing that he was an "accessory" to "doing wrong to the US tax authorities" over Mr Frampton's first US fight.
The two sports stars are locked in a legal battle over the acrimonious ending of their partnership in 2017. Mr Frampton (33) is suing his ex-manager and Cyclone Promotions for alleged withholding of earnings of up to £6m.
In a counter-suit, Mr McGuigan is claiming against the Belfast-born boxer for alleged breach of contract.
Both men deny the respective allegations against them.
Mr Frampton signed a "slave contract" after winning a high-profile world title bout in front of nearly 15,000 fans, the court was told.
He signed the deal tying him to a company linked to Mr McGuigan's Cyclone Promotions for nearly five years following the September 2014 defeat of Kiko Martinez in an outdoor clash at the Titanic Quarter, it was claimed.
Four different "public sector entities" paid "around £240,000" to the promoters of the fight, which also attracted £330,000 funding from a London company whose offices were later raided by police, it was stated.
Mr McGuigan described claims that he had Frampton tied to a slave contact as "nonsense".
The former boxer rejected allegations that the fighter was under lock and key at the height of his career to stop him from exploring other opportunities.
He also denied manipulating figures to declare a loss from Mr Frampton's world title contests staged in Belfast. "We never tried to pull the wool over Carl Frampton's eyes, ever," he said.
As his cross-examination continued on day 12 of the case, Mr McGuigan was pressed on an international promotional agreement (IPA) signed in 2015.
The court heard the deal involved the rights to Mr Frampton's fights for three years and could potentially be extended by nearly two more years.
According to counsel for the boxer, Gavin Millar QC, a clause prohibited his client from any other promotional contracts.
"It's lock and key, isn't it?" he suggested. "You might as well have put the handcuffs on him."
Mr McGuigan insisted the arrangement provided the flexibility for the boxer to work with other promoters.
"He got the very best fights available to him and he got the best money," he said.
But the barrister cited a term Mr McGuigan used in his memoir about an arrangement from his own boxing days.
"It is a slave contract, isn't it, Mr McGuigan?" he asked.
Mr McGuigan replied: "That's a nonsense comment if you look at what happened with his career. Look at the opportunities he had, look at the success he had and the amount of money that he made. That is a ridiculous comment."
It was put to him that at that point in Mr Frampton's career, having just won a world title, he could have "tested the market" for promotional opportunities.
Again, however, Mr McGuigan described the suggestion as "ridiculous" and pointed to how he guided the boxer.
"He got the very best fights out there in the division, avoided the danger men, got wonderful opportunities and made lots of money," he said.
"I don't know how I could have handled his career better, I really don't."
Mr McGuigan was told that it would have been in the boxer's interests to see what other deals were on offer.
"(The IPA) copper-bottom guaranteed cast-iron rights over the rest of his career for nearly five years," Mr Millar submitted.
He suggested the boxer might have been tempted by a "bigger, better promoter" and that the manager wanted to prevent that happening.
"It worked both ways," Mr McGuigan answered. "Obviously, we gave him the best opportunity, but I'm not sitting here and saying we didn't want to be protected ourselves, given the efforts we put in too."
The court heard details of a deal between Cyclone and CWM, a trading firm headed by an individual named in court as Anthony Constantinou.
The company invested around £330,000 in Cyclone Promotions and promised another payment of the same amount, the court heard.
For a time between the Martinez fight in September 2014 and one against Chris Avalos in late February 2015, the promotions firm linked to Mr McGuigan was named CWM Cyclone Promotions.
Police officers raided CWM's London offices in March 2015. Two of Mr McGuigan's sons, Blain and Jake, were at the office at the time of the raid but were not arrested, the court heard.
"They held them for about an hour, the boys, then let them go," Mr McGuigan told the court.
Mr McGuigan was also questioned about how much his boxer was paid for a July 2015 fight against Alejandro Gonzalez in El Paso, Texas. It was Mr Frampton's first US fight and he was told the purse would be $1m. Officials in Texas were told the prize money for Mr Frampton would be $400,000.
"You were a willing accessory to doing wrong to the US tax authorities?" Mr Millar asked. "Yes," said Mr McGuigan.
He was also questioned about money that flowed following the Quigg fight. A total of £2.4m was sent to Cyclone Promotions accounts, the court heard.
The former boxer was asked why he, as manager, charged 20% of the gross amount, approximately £491,000, when it is claimed it should have been net.
Cyclone Promotions received 10%, as did trainer Shane McGuigan, the court heard.
Questioned over why Mr Frampton was not paid until December for the Quigg event staged 10 months before, Mr McGuigan said he encouraged "the boys" - his sons Blain and Jake - to pay Mr Frampton.
Ticket sales, purse fees and sponsorship arrangements for some of the boxer's big hometown shows in Belfast also came under scrutiny.
In September 2014 Mr Frampton defeated Mr Martinez in front of a crowd of up to 15,000 in Belfast to take the IBF world super-bantamweight title.
The court heard tickets worth just over £1m in total were available for the fight, excluding 855 complimentary seats provided to Cyclone Promotions.
Mr McGuigan repeatedly said that he did not deal with the financial side of the business, focusing instead on looking after his fighters in the gym.
"I'm going to have to sound like a broken record, but that was not my domain," he added.
Referring to figures given for the contest, Mr Millar said a loss of £120,000 was reported on declared income of £1.3m.
"You manipulated the figures to make it look like this fight was loss-making, when in fact it wasn't," the barrister said.
Mr McGuigan replied: ""No, we didn't manipulate the figures, no."
The hearing continues.