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

From Tuesday, brand-new guidelines on betting entered impact in Delaware, a tiny east coast state about two hours from Washington.

Neighbouring New Jersey might begin accepting sports betting bets as early as Friday.

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

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

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

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But the market says relying on the US stays a risky bet, as UK business face complicated state-by-state guideline and competitors from established regional interests.

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

'Require time'

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

Firms are wishing to take advantage of more of that activity after last month's decision, which overruled a 1992 federal law that disallowed states beyond 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 actually legalise sports betting, leaving that question to local legislators.

That is expected to cause significant variation in how companies get accredited, where sports betting wagering can occur, and which events are open to speculation - with big ramifications for the size of the market.

Potential earnings varieties from $4.2 bn to almost $20bn every year depending upon elements like the number of states relocate 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 huge'", stated Will Hawkley, London-based head of leisure for experts KPMG.

Now, he said: "I believe the majority of people ... are looking at this as, 'it's a chance however it's not going to be $20bn and it's going to be state by state and it's going to require time'."

'Remains to be seen"

Chris Grove, managing director at Eilers & Krejcik Gaming, anticipates that 32 states will legalise sports wagering in some form by 2023, creating a market with about $6bn in yearly income.

But bookies deal with a far different landscape in America than they carry out in the UK, where betting shops are a frequent sight.

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

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

States have actually likewise been sluggish to legalise many kinds of online betting, in spite of a 2011 Justice Department opinion that appeared to remove barriers.

While sports wagering is generally viewed in its own classification, "it clearly remains to be seen whether it gets the kind of momentum individuals believe it will," said Keith Miller, law professor at Drake University and co-author of a book about sports wagering regulation.

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

Now a consultant, he says UK firms must approach the marketplace thoroughly, choosing partners with care and preventing missteps that could result in regulator reaction.

"This is an opportunity for the American sports betting wagerer ... I'm not sure whether it is an opportunity for service," he states. "It really is reliant on the result of [state] legislation and how the service operators pursue the opportunity."

'It will be partnerships'

As legalisation starts, sports betting wagering firms are lobbying to fend off high tax rates, in addition to requests by US sports betting leagues, which wish to gather a percentage of income as an "integrity cost".

International companies face the added obstacle of a powerful existing video gaming industry, with casino operators, state-run lottery games and Native American people that are looking for to safeguard their grass.

Analysts say UK firms will require to strike partnerships, offering their know-how and technology in order to make inroads.

They point to SBTech's current statement that it is offering technology for Kentucky Derby operator Churchill Downs as an example of the sort of deals likely to materialise.

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

'It will simply depend'

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

The business has been investing in the US market because 2011, when it acquired three US companies to develop an existence in Nevada.

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

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

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

"We certainly intend to have a very significant brand existence in New Jersey," he stated. "In other states, it will simply depend on policy and possibly who our local partner is."

"The US is going to be the most significant sports betting market worldwide," he included. "Obviously that's not going to occur on the first day."