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

From Tuesday, new rules on wagering came into impact 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 changes are the very 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 market sees a "as soon as in a generation" opportunity 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 grappling with combination, increased online competition and tougher guidelines from UK regulators, the timing is especially appropriate.

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But the industry states counting on the US remains a risky bet, as UK business face complex state-by-state regulation and competitors from entrenched local interests.

"It's something that we're actually concentrating on, but equally we do not want to overhype it," stated James Midmer, spokesman at Paddy Power Betfair, which just recently acquired the US dream sports 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 take advantage of more of that activity after last month's decision, which struck down a 1992 federal law that barred states outside of Nevada and a few others from authorising sports betting.

The judgment found the law was an over-reach of federal power. But the court it did not in fact legalise sports betting, leaving that concern to regional lawmakers.

That is expected to result in significant variation in how firms get accredited, where sports betting can take place, and which occasions are open to speculation - with huge ramifications for the size of the marketplace.

Potential earnings varieties from $4.2 bn to nearly $20bn each year depending on elements like how numerous states move to legalise, Oxford Economics estimated 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 experts KPMG.

Now, he said: "I think 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, managing director at Eilers & Krejcik Gaming, forecasts that 32 states will legalise sports wagering in some form by 2023, developing a market with about $6bn in yearly revenue.

But bookmakers face a far various landscape in America than they carry out in the UK, where wagering shops are a frequent sight.

US laws limited betting mostly to Native American lands and Nevada's Las Vegas strip till relatively recently.

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

States have actually likewise been sluggish to legalise many forms of online gaming, regardless of a 2011 Justice Department opinion that appeared to remove obstacles.

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

David Carruthers is the previous 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 market carefully, picking partners with caution and avoiding missteps that might cause regulator reaction.

"This is a chance for the American sports gambler ... I'm not sure whether it is a chance for company," he states. "It really is reliant on the outcome of [state] legislation and how business operators pursue the chance."

'It will be partnerships'

As legalisation starts, sports betting firms are lobbying to fend off high tax rates, as well as demands by US sports leagues, which want to collect a portion of profits as an "integrity charge".

International companies deal with the added difficulty of an effective existing video gaming industry, with casino operators, state-run lottery games and Native American people that are seeking to safeguard their grass.

Analysts say UK companies will require to strike partnerships, using their proficiency and innovation in order to make inroads.

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

"It will be a win-win for everybody, however it will be partnerships and it will be driven by technology," Mr Hawkley stated.

'It will just depend'

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

The business has been investing in the US market given that 2011, when it acquired three US firms to develop an existence in Nevada.

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

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

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

"We certainly intend to have a very significant brand name 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 biggest sports wagering market worldwide," he added. "Obviously that's not going to take place on the first day."