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

From Tuesday, brand-new rules on wagering came into result in Delaware, a tiny east coast state about 2 hours from Washington.

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

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

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

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

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But the market says relying on the US remains a risky bet, as UK companies deal with complex state-by-state guideline and competitors from established regional interests.

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

'Require time'

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

Firms are intending to tap into more of that activity after last month's decision, which overruled a 1992 federal law that disallowed states beyond Nevada and a couple of others from authorising sports wagering.

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

That is expected to cause substantial variation in how firms get accredited, where sports betting can happen, and which occasions are open to speculation - with big implications for the size of the marketplace.

Potential revenue varieties from $4.2 bn to almost $20bn each year depending on elements like the number of states transfer to legalise, Oxford Economics approximated in a 2017 study for the American Gaming Association.

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

Now, he said: "I think the majority of people ... 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, managing director at Eilers & Krejcik Gaming, anticipates that 32 states will legalise sports betting in some form by 2023, developing a market with about $6bn in yearly earnings.

But bookies face a far various landscape in America than they perform in the UK, where betting shops are a regular sight.

US laws limited gambling largely to Native American lands and Nevada's Las Vegas strip until relatively just recently.

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

States have actually also been slow to legalise many kinds of online betting, despite a 2011 Justice Department opinion that appeared to eliminate barriers.

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

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 an expert, he says UK companies must approach the market thoroughly, selecting partners with care and avoiding missteps that might result in regulator reaction.

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

'It will be collaborations'

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

International business deal with the added challenge of an effective existing gaming market, with gambling establishment operators, state-run lottos and Native American tribes that are looking for to defend their turf.

Analysts state UK firms will require to strike collaborations, offering their competence and innovation in order to make inroads.

They point to SBTech's current statement that it is supplying technology for Kentucky Derby operator Churchill Downs as an example of the sort 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 innovation," 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 buying the US market given that 2011, when it purchased 3 US companies to establish a presence in Nevada.

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

It works as risk manager 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 become a family name in Nevada but that's not necessarily the goal everywhere.

"We certainly mean to have a very significant brand existence in New Jersey," he stated. "In other states, it will simply depend upon policy and potentially who our regional partner is."

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