Northampton have signed Wigan Warriors' teenage full-back Chris Ashton on a three-year contract from next season.
Wigan full-back Ashton will join Saints in the summer
Ashton, 19, has taken Super League by storm since his debut in 2005 and was Wigan's first-choice last year, making 29 appearances and scoring 15 tries.
"He's a hugely exciting prospect," said Saints boss Paul Grayson.
"He's making the move already having made a huge impact in league. And with time on his side he's going to make an equally big impact in union."
Ashton was selected for England's rugby league team in the 2006 Federation Shield tournament and toured with the victorious England Academy Under-18 squad in Australia.
But he is looking forward to playing in the 15-a-side version of the game.
It's disappointing that rugby league has lost another talented outside back
"Rugby union is a massive sport across the world," he said. "You just have to look at how big it was when England won the World Cup.
"Northampton is one of the biggest clubs in the country with a great history and a great future as well. You just have to look at what is around Franklin's Gardens to appreciate that.
"It will be a steep learning curve but they have everything at Northampton to help me achieve success. They're building a squad of young English talent and the next few years could be really exciting."
Wigan chairman Maurice Lindsay and coach Brian Noble admitted there was no way the Warriors could compete financially with what was on offer from rugby union.
Noble said: "The club has tried extremely hard to convince him his future is in rugby league.
"I am not sure at this stage of his career whether Chris is making the right decision, however we wish him well for the future.
"It's disappointing that rugby league has lost another talented outside back."
Lindsay added: "We put forward an offer to (Ashton's agent) Andrew Clarke for a contract to take Chris through to 2009 with a built-in promise we would revisit the contract if Chris made the required progress.
"The contract we offered would have been higher than the contracts agreed by Sean O'Loughlin and Gareth Hock at the same age and stage of their careers.
"We heard nothing more for two weeks but we were then advised by Andrew Clarke that Chris would be joining Northampton rugby union club on a salary of £140,000 per year.
"Brian Noble, quite understandably, did not want to spend £140,000 out of a salary cap limit of £1.6m on a young player who was still in a stage of development."
Ashton is the latest youngster to switch codes, following in the footsteps of Karl Pryce (Bradford), Stephen Myler (Salford) and Chev Walker (Leeds).
They moved at the end of the last season, joining Gloucester, Northampton and Bath respectively.
Ashton is also the latest Wigan player to switch codes, following the likes of Jason Robinson and Andy Farrell, while former Wigan winger Brian Carney joined Munster last week.