Floyd "Money" Mayweather is gearing up for what's been dubbed the fight of the century. And while it will no doubt demonstrate his boxing prowess, the huge paycheck is also a testament to his business acumen.
"I had a business plan. I was brilliant, I was smart ... and here we are in the fight on the century," he recently told the LA Times.
Mayweather is worth about $280m (£185m). He's amassed a fortune $400m (£264) through his career to-date. And yet his endorsements earn him a big fat zero, largely due to his shameful record of domestic abuse.
However, this hasn't stopped him from frequently topping the Forbes list of richest sports stars. His $105m (£694m) paycheck mean he held onto the top spot again last year.
So how has he managed to become the world's best paid sports star?
When Mayweather meets Pacquiao in the ring tonight, he won't just the star of the show, but also the brains behind it. That's because he effectively acts as his own promoter, and this unique business model sees him negotiate the financial arrangements for the mega-fights which make him millions.
It means that whenever Mayweather fights, he doesn't just collect a fee, but also makes money from all aspects of the events he puts on, from the ticket sales, right down to the food and drink.
It's a sharp contrast to some of the world's top-grossing athletes who rely largely on endorsements. The world's second best paid sports star footballer Cristiano Ronaldo made $23m from endorsements last year while, basket ball player LeBron James made $53m. The figures dwarfed their respective salaries.
Mayweather was first helped onto the road to riches by Harvard economics graduate Al Haymon who helped him negotiate his way out of his contract with Top Rank for $750,000 in 2006.
Since then he's scored a series of huge pay days. He made $42m from his fight with Saul Alvarez in September 2013, the following year raking in a total of $64m from his two fights with Marcos Maidana.