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

From Tuesday, new rules on betting came into effect in Delaware, a small east coast state about two hours from Washington.

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

The modifications are the very first in what might become a wave of legalisation after the Supreme Court last month cleared the method for states to allow sports betting.

The market sees a "as soon as 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 companies, which are facing consolidation, increased online competition and tougher guidelines from UK regulators, the timing is particularly appropriate.

Why the betting industry faces an unsure future

How does illegal sports betting work and what are the worries?

But the market says counting on the US stays a dangerous bet, as UK business face complex state-by-state policy and competitors from established local interests.

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

'Take time'

The US represented 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 hoping 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 couple of others from authorising sports betting.

The judgment discovered 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 considerable variation in how firms get accredited, where sports wagering can happen, and which occasions are open to speculation - with big ramifications for the size of the market.

Potential earnings ranges from $4.2 bn to practically $20bn each year depending on factors like how many states transfer to legalise, Oxford Economics estimated in a 2017 research study for the American Gaming Association.

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

Now, he stated: "I think a lot of individuals ... 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 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, creating a market with about $6bn in yearly earnings.

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

US laws minimal gaming largely to Native American lands and Nevada's Las Vegas strip until relatively recently.

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

States have actually also been slow to legalise numerous forms of online betting, regardless of a 2011 Justice Department viewpoint that appeared to get rid of obstacles.

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

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

Now a specialist, he states UK companies need to approach the marketplace thoroughly, picking partners with care and avoiding mistakes that could lead to regulator reaction.

"This is an opportunity for the American sports bettor ... I'm uncertain whether it is an opportunity for organization," he states. "It actually is reliant on the result of [state] legislation and how business operators pursue the opportunity."

'It will be collaborations'

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

International business deal with the added difficulty of a powerful existing gaming industry, with casino operators, state-run lotteries and Native American tribes that are looking for to safeguard their grass.

Analysts say UK companies will require to strike collaborations, offering their expertise and technology in order to make inroads.

They indicate SBTech's current announcement that it is supplying innovation for Kentucky Derby operator Churchill Downs as an example of the kind of offers likely to materialise.

"It will be a win-win for everybody, but it will be partnerships and it will be driven by technology," 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 purchasing the US market considering that 2011, when it acquired three US companies to establish an existence in Nevada.

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

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

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

"We certainly intend to have an extremely considerable brand name existence in New Jersey," he said. "In other states, it will simply depend upon guideline and possibly who our local partner is."

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