NFL superstar Matthew Stafford’s whirlwind trip to Melbourne has sparked speculation he could lose more than half his match pay to tax.

The Los Angeles Rams quarterback arrived barely a day before Friday’s historic showdown with the San Francisco 49ers at the MCG.

But before Stafford had thrown a pass, a viral calculation claiming he faced a $960,000 Australian tax bill had put his earnings under the spotlight.

American football account MLFootball estimated the quarterback would pocket just $947,000 from $2.2million in Week 1 income after Australian and American taxes.

‘Nearly 57 per cent of the $2.2 million will go to taxes,’ the account claimed.

The post estimated Stafford’s tax bill at approximately $1.25million, including Australian tax and $293,000 in California tax, with US federal liabilities offset by foreign tax credits.

Matthew Stafford became the focus of tax bill claims before the Rams faced San Francisco at the MCG

A viral estimate claimed Stafford faced $960,000 in Australian tax, but the ATO did not confirm that figure

However, the Australian figure remains an estimate, with an accountant questioning the calculation and the ATO declining to discuss Stafford’s personal affairs.

The tax office did confirm that overseas athletes generally face withholding tax on payments for sporting activities performed in Australia.

‘This means that amounts are required to be withheld from payments made to foreign residents in relation to their sports and related activities,’ an ATO spokesperson told news.com.au.

The spokesperson said athletes with deductible expenses could apply to vary their withholding rate. Foreign tax credits could also offset tax liabilities back home.

Tax Invest Accounting director Belinda Raso said the viral calculation did not establish what Stafford would actually owe.

‘That’s just their assumption at the 45 per cent tax rate. It doesn’t automatically go straight to that, we do have a sliding tax scale,’ she told news.com.au.

‘But it’s massive numbers that we’re talking about. If you’re earning that much, it’s a big cut of your income. The main thing is you’ve got to take work-related expenses out.’

Raso said the final amount would depend on how much income was attributed to Stafford’s time in Australia, along with relevant deductions.

The Rams arrived in Melbourne approximately 28 hours before kickoff, while San Francisco allowed a week to acclimatise

The MCG hosted Australia’s first regular-season NFL game, with the Rams and 49ers bringing their rivalry to Melbourne

Tax Invest Accounting director Belinda Raso said the viral calculation did not establish what Stafford would actually owe

The tax debate adds another talking point to a trip that has already divided opinion over the teams’ sharply different travel plans.

The 49ers gave themselves a week to settle into Melbourne, training at AAMI Park and meeting supporters around the city.

The Rams arrived approximately 28 hours before kickoff following a 16-hour flight, then trained at Marvel Stadium.

Their approach was intended to maintain the players’ routine and manage jet lag, but receiver Davante Adams admitted he wished there had been more time for Australian fans.

‘Obviously we would love to have the opportunity to connect with the fans out here a little bit more,’ Adams said.

He said players had ventured out after landing, with Stafford finding time to sample Melbourne’s coffee.

‘We did as much as we could with our travel schedule,’ Adams said.

The long journey had already drawn criticism from 49ers coach Kyle Shanahan, who questioned the competitive benefit of flying across the world for the fixture.

While players prepared for Australia’s first regular-season NFL game, Melbourne businesses were anticipating a busy weekend.

NAB forecast more than $300million in spending across hotels, restaurants, pubs and retailers, with the Victorian government estimating as many as 7,000 Americans had made the trip.

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