Asamoah Gyan will join the Pro League champions on a permanent basis for the start of the upcoming season after terms are agreed upon with Sunderland and the Ghana international.
Al Ain keep their man as Asamoah Gyan permanently transferred from Sunderland
The 26-year-old Ghana international, who earned 3million (Dh13.6m) during a loan spell with the UAE Pro League champions last season, has signed a four-year contract for undisclosed terms.
It is understood Al Ain paid the Black Cats around £6million for Gyan's temporary stay and will hand over a similar fee to secure his services on a long-term basis.
A Sunderland statement said: "Sunderland AFC can confirm that Ghana international Asamoah Gyan has joined United Arab Emirates side Al-Ain on a permanent deal.
"The striker initially joined the recently-crowned Pro League champions on loan in September 2011 but will now remain in the Gulf state after the clubs agreed undisclosed terms."
The news comes as no surprise after the UAE club's chief executive Carlo Nohra indicated earlier this week that an announcement was imminent.
However, it ends a sorry period in the Black Cats' recent history as a player then-manager Steve Bruce thought would help to bring long-term success to the club departed just two years after his arrival.
Gyan completed a £13million-plus switch to the Stadium of Light from French side Rennes just weeks after starring for his country at the 2010 World Cup finals in South Africa, where his extra-time penalty miss against Uruguay had cost them a place in the last four.
He was signed on a four-year contract to play alongside Darren Bent, but their partnership was still in its infancy when the England international sealed a shock January move to Aston Villa.
The African scored 11 goals in his first season in English football and was also on target for his country in a 1-1 friendly draw with England as his reputation blossomed to the extent that he was linked with a summer move away from Wearside.
However, after months of speculation, Bruce was stunned to learn that Gyan had been tempted by the offer of a lucrative loan move to the UAE and reluctantly allowed him to leave in September last year as Sunderland cut their losses.
The frontman scored 22 goals as Al Ain claimed the title and with Bruce's replacement Martin O'Neill admitting he did not expect the player to return, his exit was inevitable.
O'Neill has been actively involved in the search for striking talent in recent months with loan signing Nicklas Bendtner having returned to parent club Arsenal, and has been heavily linked with Wolves' Steven Fletcher.
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