Tottenham Hotspur manager Harry Redknapp went on trial on Monday accused of receiving offshore bungs from his former employer.
The 64-year-old - tipped as a future England boss - dodged taxes on "substantial payments" while he was in charge at Portsmouth, a jury heard.
Appearing in the dock, Redknapp stood accused of receiving two untaxed payments of more than £189,000 from former chairman Milan Mandaric, his co-accused.
John Black QC opened the Crown's case at Southwark Crown Court by telling jurors "both parties must have known" they were avoiding taxes.
"These payments were a bung or offshore bonus that the parties had absolutely no intention of paying taxes for," he said.
Redknapp's "widespread popularity" was singled out by the prosecution. "He is currently enjoying what may be described as footballing success," Mr Black said.
"They (Tottenham) are currently riding high and are placed today as third in the league despite yesterday's result."
Redknapp, appearing behind bullet-proof glass alongside Mandaric, read notes as Mr Black outlined how the manager received player transfer bonuses under a clause in his contract.
Mr Black focused on the purchase of Peter Crouch for £1,250,000 before he was sold for £4.5 million.
Redknapp and Mandaric deny two counts of cheating the public revenue when he was manager of Portsmouth.
The first charge alleges that between April 1, 2002 and November 28, 2007 Mandaric paid 145,000 US dollars (£93,100) into a bank account held by Redknapp in Monaco to avoid paying income tax and National Insurance.
The second charge for the same offence relates to a sum of 150,000 US dollars (£96,300) allegedly paid by Mandaric to the same account between May 1, 2004 and November 28, 2007.
Redknapp who underwent minor heart surgery last year to unblock his arteries, is the most successful English manager in the modern game, having led Portsmouth to FA Cup success and Spurs to last season's Champions League quarter-finals.
Serbian Mandaric, 73, is now chairman of Sheffield Wednesday, having previously worked at Leicester.
Redknapp, of Panorama Drive, Poole, Dorset, is represented by John Kelsey-Fry QC, while Lord Macdonald QC is counsel for Mandaric, of Stretton Hall, Oadby, Leicestershire.
Redknapp was described as a "hard-headed businessman" as the jury of eight men and four women were shown a string of documents and his signature.
Bonuses paid to Redknapp during his time at the club would total up to £500,000 depending on profits the club made on player transfers, Mr Black added.
"Harry Redknapp was, it goes without saying, no ordinary employee," Mr Black said.
He had the "greatest capacity to influence the success or failure of his football club", he added.
The barrister said: "Talented and popular he might have been, the Crown say he was nevertheless a hard-headed businessman, with a financial acumen and pecuniary sense of his influence to his employers."
Redknapp initially received 10% of net profit made on player transfers made during his time as part of a clause in his contract, Mr Black said.
"He had a highly lucrative employment contract," he said.
His contract later changed and it was reduced to 5%, the barrister said. He was paid about £100,000 when England striker Crouch left the south-coast club for Aston Villa in 2002, the court heard.
Redknapp never mentioned the Monaco account as he was investigated by HM Revenue and Customs officials over his transfer dealings at West Ham, the court heard.
The probe, between January 2004 and October 2006, "was originally prompted by concerns over a £300,000 payment... regarding profit made in a player transfer, namely Rio Ferdinand", Mr Black said.
The Monaco bank account eventually came to light during an inquiry into illicit payments in football, led by Lord Stevens, the former Metropolitan Police Commissioner.
The investigation, dubbed the Quest inquiry, was handed to the Premier League chief executive Richard Scudamore in July 2007.
In November the previous year, Redknapp had been interviewed as part of the investigation.
"That was the first time anyone heard of a Monaco bank account," the barrister said.