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

From Tuesday, new guidelines on wagering entered impact in Delaware, a tiny east coast state about 2 hours from Washington.

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

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

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

For UK firms, which are coming to grips with debt consolidation, increased online competition and harder guidelines from UK regulators, the timing is particularly appropriate.

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But the market states depending on the US remains a dangerous bet, as UK business face complicated state-by-state policy and competitors from established local interests.

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

'Require time'

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

Firms are hoping to tap into more of that activity after last month's decision, which overruled a 1992 federal law that disallowed states outside of Nevada and a few others from authorising sports betting 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 concern to local lawmakers.

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

Potential earnings ranges from $4.2 bn to nearly $20bn annually depending upon aspects like how many states relocate 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'", said Will Hawkley, London-based head of leisure for specialists KPMG.

Now, he said: "I believe the majority of people ... are looking at this as, 'it's an opportunity however 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, anticipates that 32 states will legalise sports wagering in some form by 2023, developing a market with about $6bn in annual income.

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

US laws minimal gambling mainly to Native American lands and Nevada's Las Vegas strip until reasonably recently.

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

States have also been sluggish to legalise numerous types of online gaming, in spite of a 2011 Justice Department opinion that appeared to remove obstacles.

While sports betting is typically viewed in its own classification, "it plainly stays to be seen whether it gets the kind of momentum people believe it will," said Keith Miller, law teacher at Drake University and co-author of a book about sports wagering guideline.

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

Now an expert, he says UK firms ought to approach the marketplace carefully, selecting partners with caution and preventing bad moves that could lead to regulator reaction.

"This is an opportunity for the American sports wagerer ... I'm unsure whether it is an opportunity for service," he states. "It truly depends on the result of [state] legislation and how business operators pursue the opportunity."

'It will be partnerships'

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

International companies face the added obstacle of an effective existing gaming market, with casino operators, state-run lotteries and Native American people that are looking for to safeguard their turf.

Analysts say UK firms will need to strike collaborations, offering their knowledge and innovation in order to make inroads.

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

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

'It will simply depend'

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

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

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

It works as risk manager for the Delaware Lottery and has actually invested millions together with a local developer in a New Jersey horse racing track.

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

"We certainly intend to have an extremely significant brand name presence in New Jersey," he said. "In other states, it will just depend upon policy and potentially who our local partner is."

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