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

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

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

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

The industry sees a "once in a generation" opportunity to establish a new market in sports betting-mad America, said Dublin-based monetary expert David Jennings, who heads leisure research at Davy.

For UK companies, which are grappling with consolidation, increased online competition and harder guidelines from UK regulators, the timing is particularly opportune.

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But the industry says relying on the US remains a dangerous bet, as UK business deal with complicated state-by-state policy and competition from entrenched local interests.

"It's something that we're truly focusing on, but equally we do not wish to overhype it," said James Midmer, spokesperson at Paddy Power Betfair, which recently acquired the US dream sports site FanDuel.

'Take time'

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

Firms are wanting to take advantage of more of that activity after last month's decision, which struck down a 1992 federal law that disallowed 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 wagering, leaving that question to local legislators.

That is expected to cause significant variation in how firms get accredited, where sports betting wagering can happen, and which events are open to speculation - with huge implications for the size of the market.

Potential profits varieties from $4.2 bn to nearly $20bn every year depending on factors like how lots of states relocate to legalise, Oxford Economics approximated in a 2017 study for the American Gaming Association.

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

Now, he said: "I think the majority of people ... are taking a look at this as, 'it's a chance but 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, predicts that 32 states will legalise sports betting wagering in some form by 2023, producing a market with about $6bn in annual income.

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

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

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

States have actually also been sluggish to legalise many types of online gambling, despite a 2011 Justice Department viewpoint that appeared to get rid of challenges.

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

David Carruthers is the previous president of BetonSports, who was detained in the US in 2006 for running an overseas online sportsbook and served jail time.

Now an expert, he states UK companies should approach the marketplace thoroughly, picking partners with caution and avoiding bad moves that might lead to regulator backlash.

"This is a chance for the American sports betting gambler ... I'm uncertain whether it is a chance for organization," he says. "It truly is dependent on the result of [state] legislation and how the organization operators pursue the opportunity."

'It will be partnerships'

As legalisation starts, sports wagering firms are lobbying to fend off high tax rates, along with requests by US sports betting leagues, which wish to collect a percentage of income as an "integrity charge".

International companies deal with the added obstacle of a powerful existing gaming market, with gambling establishment operators, state-run lottos and Native American people that are seeking to protect their grass.

Analysts say UK firms will need to strike partnerships, using their expertise and technology in order to make inroads.

They point to SBTech's recent announcement that it is supplying technology for Kentucky Derby operator Churchill Downs as an example of the sort of offers most likely to materialise.

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

'It will simply depend'

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

The business has been investing in the US market since 2011, when it purchased three US companies to develop a presence in Nevada.

William Hill now employs about 450 individuals in the US and has actually announced collaborations with gambling establishments in Iowa and New Jersey.

It works as danger manager for the Delaware Lottery and has invested millions together with a regional designer in a New Jersey horse racing track.

Mr Asher stated William Hill has become a family name in Nevada however that's not always the objective everywhere.

"We definitely plan to have a very considerable brand name existence in New Jersey," he said. "In other states, it will simply depend upon policy and potentially who our regional partner is."

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