It's high stakes for UK firms as sports wagering starts to spread in America.

From Tuesday, brand-new rules on betting entered into effect in Delaware, a tiny east coast state about 2 hours from Washington.

Neighbouring New Jersey could begin accepting sports bets as early as Friday.

The changes are the first in what could become a wave of legalisation after the Supreme Court last month cleared the way for states to enable sports wagering.

The industry sees a "when in a generation" opportunity to develop a new market in sports-mad America, stated Dublin-based financial expert David Jennings, who heads leisure research at Davy.

For UK firms, which are facing debt consolidation, increased online competitors and tougher rules from UK regulators, the timing is particularly suitable.

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But the industry states relying on the US stays a dangerous bet, as UK business deal with complex state-by-state regulation and competition from established local interests.

"It's something that we're truly concentrating on, however equally we don't desire to overhype it," stated James Midmer, spokesman at Paddy Power Betfair, which just recently purchased the US fantasy sports betting website FanDuel.

'Require time'

The US represented about 23% of the world's $244bn (₤ 182bn) in gaming income in 2015, according to a report by Technavio, external published in January.

Firms are wishing to use more of that activity after last month's decision, which struck down a 1992 federal law that disallowed states beyond Nevada and a couple of others from authorising sports wagering.

The ruling found the law was an over-reach of federal power. But the court it did not in fact legalise sports wagering, leaving that question to local legislators.

That is anticipated to result in substantial variation in how firms get accredited, where sports betting can occur, and which events are open to speculation - with huge ramifications for the size of the market.

Potential income ranges from $4.2 bn to nearly $20bn every year depending on aspects like how numerous states transfer to legalise, Oxford Economics estimated in a 2017 study for the American Gaming Association.

"There was a great deal of 'this is going to be substantial'", said Will Hawkley, London-based head of leisure for consultants KPMG.

Now, he stated: "I believe the majority of individuals ... are looking at this as, 'it's an opportunity but it's not going to be $20bn and it's going to be state by state and it's going to take time'."

'Remains to be seen"

Chris Grove, handling director at Eilers & Krejcik Gaming, forecasts that 32 states will legalise sports wagering in some type by 2023, creating a market with about $6bn in annual revenue.

But bookies deal with a far various landscape in America than they carry out in the UK, where wagering shops are a regular sight.

US laws limited gaming largely to Native American lands and Nevada's Las Vegas strip until reasonably recently.

In the popular imagination, sports betting has long been connected to a 1919 baseball World Series match-fixing scandal.

States have also been slow to legalise numerous types of online gambling, in spite of a 2011 Justice Department viewpoint that appeared to remove challenges.

While sports wagering is normally viewed in its own classification, "it clearly stays to be seen whether it gets the type of momentum people think it will," stated Keith Miller, law teacher at Drake University and co-author of a book about sports wagering guideline.

David Carruthers is the former primary executive of BetonSports, who was arrested in the US in 2006 for running an overseas online sportsbook and served prison time.

Now a specialist, he states UK firms ought to approach the marketplace carefully, picking partners with care and preventing mistakes that could cause regulator backlash.

"This is a chance for the American sports bettor ... I'm unsure whether it is an opportunity for business," he says. "It actually depends on the result of [state] legislation and how business operators pursue the opportunity."

'It will be partnerships'

As legalisation starts, sports wagering companies are lobbying to ward off high tax rates, along with demands by US sports leagues, which wish to collect a portion of earnings as an "integrity fee".

International companies deal with the added challenge of a powerful existing gaming market, with casino operators, state-run lotteries and Native American tribes that are looking for to safeguard their grass.

Analysts say UK companies will require to strike collaborations, using their proficiency and innovation in order to make inroads.

They indicate SBTech's current announcement that it is supplying innovation for Kentucky Derby operator Churchill Downs as an example of the kind of deals likely to materialise.

"It will be a win-win for everybody, however it will be collaborations and it will be driven by technology," Mr Hawkley said.

'It will just depend'

Joe Asher, primary executive at William Hill US, is clear-eyed about the realities.

The business has been purchasing the US market considering that 2011, when it purchased 3 US firms to establish an existence in Nevada.

William Hill now employs about 450 individuals in the US and has revealed collaborations with casinos in Iowa and New Jersey.

It works as risk supervisor for the Delaware Lottery and has actually invested millions along with a regional designer in a New Jersey horse racing track.

Mr Asher said William Hill has become a household name in Nevada but that's not necessarily the objective everywhere.

"We certainly mean to have an extremely considerable brand name presence in New Jersey," he stated. "In other states, it will just depend upon regulation and possibly who our local partner is."

"The US is going to be the biggest sports wagering market worldwide," he included. "Obviously that's not going to happen on the first day."