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

From Tuesday, new guidelines on betting came into effect in Delaware, a tiny 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 might end up being a wave of legalisation after the Supreme Court last month cleared the way for states to permit sports betting.

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

For UK companies, which are coming to grips with debt 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 stays a risky bet, as UK companies face complex state-by-state policy and competitors from entrenched local 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 acquired the US dream sports betting site FanDuel.

'Take time'

The US represented about 23% of the world's $244bn (₤ 182bn) in gaming earnings last year, according to a report by Technavio, external released 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 judgment found the law was an over-reach of federal power. But the court it did not really legalise sports betting, leaving that question to local legislators.

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

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

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

Now, he stated: "I believe many people ... are taking a look 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 some time'."

'Remains to be seen"

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

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

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

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

States have likewise been slow to legalise lots of kinds of online gambling, despite a 2011 Justice Department opinion that appeared to get rid of barriers.

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

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

Now an expert, he states UK companies should approach the marketplace carefully, picking partners with care and preventing missteps that could cause regulator backlash.

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

'It will be collaborations'

As legalisation begins, sports wagering companies are lobbying to fend off high tax rates, in addition to demands by US sports leagues, which want to gather a portion of income as an "stability fee".

International companies deal with the included challenge of a powerful existing gaming industry, with gambling establishment operators, state-run lottery games and Native American tribes that are seeking to protect their turf.

Analysts state UK firms will need to strike partnerships, providing their knowledge and technology in order to make inroads.

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

"It will be a win-win for everyone, however 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 business has actually been investing in the US market since 2011, when it bought three US firms to develop an existence in Nevada.

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

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

Mr Asher stated William Hill has ended up being a family name in Nevada but that's not always the goal everywhere.

"We definitely plan to have a really significant brand name presence in New Jersey," he said. "In other states, it will simply depend on regulation and possibly who our local partner is."

"The US is going to be the greatest sports betting market on the planet," he added. "Obviously that's not going to happen on the first day."