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

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

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

The changes are the first in what could end up being a wave of legalisation after the Supreme Court last month cleared the way for states to permit sports betting.

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

For UK firms, which are facing combination, increased online competition and harder rules from UK regulators, the timing is especially appropriate.

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But the industry states depending on the US remains a dangerous bet, as UK companies deal with complicated state-by-state guideline and competitors from established regional interests.

"It's something that we're actually concentrating on, but equally we do not wish to overhype it," stated James Midmer, representative at Paddy Power Betfair, which recently bought the US dream sports website FanDuel.

'Take some time'

The US represented about 23% of the world's $244bn (₤ 182bn) in video gaming earnings 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 choice, which overruled a 1992 federal law that barred states outside of Nevada and a few others from authorising sports betting.

The ruling discovered the law was an over-reach of federal power. But the court it did not really legalise sports betting, leaving that question to local lawmakers.

That is expected to result in substantial variation in how companies get licensed, where sports betting can take place, and which events are open to speculation - with huge ramifications for the size of the market.

Potential revenue varieties from $4.2 bn to nearly $20bn annually depending on aspects like how many states transfer to legalise, Oxford Economics approximated in a 2017 research study for the American Gaming Association.

"There was a lot of 'this is going to be substantial'", stated Will Hawkley, London-based head of leisure for specialists KPMG.

Now, he said: "I believe the majority of people ... are taking a look 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, predicts that 32 states will legalise sports wagering in some form by 2023, developing a market with about $6bn in annual profits.

But bookmakers deal with a far different landscape in America than they do in the UK, where betting stores are a frequent sight.

US laws restricted betting largely to Native American lands and Nevada's Las Vegas strip until fairly just recently.

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

States have actually likewise been slow to legalise many types of online gambling, in spite of a 2011 Justice Department viewpoint that appeared to remove barriers.

While sports wagering is usually seen in its own category, "it plainly remains to be seen whether it gets the type of momentum people think it will," said Keith Miller, law teacher at Drake University and co-author of a book about sports betting policy.

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

Now a specialist, he says UK companies should approach the marketplace thoroughly, selecting partners with caution and preventing mistakes that might cause regulator reaction.

"This is a chance for the American sports bettor ... I'm not exactly sure whether it is an opportunity for business," he states. "It truly is reliant on the result of [state] legislation and how business operators pursue the opportunity."

'It will be partnerships'

As legalisation begins, sports betting firms are lobbying to ward off high tax rates, along with requests by US sports leagues, which wish to collect a percentage of revenue as an "integrity cost".

International companies face the included difficulty of a powerful existing gaming market, with gambling establishment operators, state-run lotteries and Native American people that are seeking to protect their turf.

Analysts say UK companies will require to strike partnerships, offering their knowledge and innovation in order to make inroads.

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

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

'It will simply depend'

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

The company has actually been purchasing the US market because 2011, when it bought 3 US companies to develop an existence in Nevada.

William Hill now employs about 450 people in the US and has revealed partnerships with gambling establishments in Iowa and New Jersey.

It works as threat supervisor for the Delaware Lottery and has actually invested millions along with a local developer in a New Jersey horse racing track.

Mr Asher said William Hill has ended up being a home name in Nevada however that's not necessarily the goal everywhere.

"We certainly intend to have a really considerable brand existence in New Jersey," he stated. "In other states, it will simply depend upon guideline and potentially who our regional partner is."

"The US is going to be the greatest sports betting market on the planet," he included. "Obviously that's not going to take place on day one."