Wales and Dragons back Haldane Luscombe has signed a two-year deal with English first division champions Harlequins.
Luscombe was seen as crucial to the Dragons' ambitions
The 15-cap centre cum wing, 25, who started every Six Nations match this year, moves at the end of the season.
South Africa-born Luscombe has been at Rodney Parade for seven years, but has grown frustrated with the Gwent side.
"I needed a fresh challenge and playing in the Guinness Premiership next season will provide me with that," Luscombe told the South Wales Argus.
"I've been at Rodney Parade for the past seven years and have played under six different coaches in that time, I've loved playing for Newport and the Dragons.
"My decision might have been different had [former Dragons benefactor] Tony Brown still been there, though my decision to join Harlequins [where Brown has a hospitality box] is nothing to do with him.
"Harlequins have got a good bunch of players. They've done extremely well in the first division and I'm looking forward to playing in an exciting back division with Stuart Abbott and Andrew Mehrtens.
"I'll miss not playing in the Heineken Cup, but moving to England shouldn't hamper my international career if I can produce the goods - it hasn't affected Colin Charvis or Mark Taylor."
Luscombe and Abbott will form a formidable partnership
Luscombe knows England centre Abbott - who secured a move to the Stoop from Wasps earlier this week - from their school days in South Africa.
With Harlequins clinching promotion this season, the pair will form a formidable partnership in the Guinness Premiership.
Dragons coach Paul Turner said last week that securing a new deal for Luscombe - whose present contract runs out in the summer - was vital to the ambitions of the region.
The burly Cape Town man was first brought to Wales by former national coach Graham Henry, who wanted to place him on a scholarship before he qualified for Wales by residency.
A media backlash scuppered that plan, and Brown put the then-18-year-old to work in his furniture factory.
His reputation has steadily grown, and the clamber for his signature increased when he put in an outstanding, try-scoring performance in this month's loss to France.