Asamoah Gyan has completed a permanent move from Sunderland to Al-Ain after flying out to United Arab Emirates to negotiate terms.
The striker had been on loan at Al-Ain since September 2011.
Gyan, 26, scored 11 goals in 37 appearances for the Black Cats after
joining from Rennes in a club-record £13m deal in August 2010.
The fee is undisclosed but Sunderland are believed to have recouped almost all of their initial outlay.
Al-Ain paid £6m for the Ghana international's initial loan spell and Sunderland are receiving a similar amount for the permanent transfer.
"Moving to the UAE was a bit controversial but I was able to prove what I am capable of doing," Gyan said before the deal was completed. "My team won the league, I was the best player, top scorer and I had a perfect season.
"This season will be a bit difficult for me. Most of the defenders will be very strong on me. My tactic this season is just to be fit and the quality will be there and it will show."
Sunderland manager Martin O'Neill revealed in April
that the 26-year-old did not want to return to Wearside.
Gyan enjoyed a successful loan period at Al-Ain, scoring 19 goals to finish top scorer as his club won the league championship
"You wouldn't really want somebody who is unwilling to come back to the football club," said the Black Cats boss. "It seems to be the message that's coming across."
When Gyan left Sunderland for the UAE in September,
the club's then-manager Steve Bruce claimed "parasites" turned the player's head
after his goal in the
1-1 draw with England at Wembley in March 2011.
Gyan's permanent move leaves O'Neill short on goalscoring options, with Fraizer Campbell, Ji Dong-Won and Connor Wickham his only recognised strikers.
Nicklas Bendtner has returned to Arsenal after scoring eight goals during a loan spell last season, while attacking midfielders Seb Larsson and Stephane Sessegnon chipped in with eight strikes each as the club relied on goals from other areas of the pitch.
Speaking at the end of last season, O'Neill acknowledged he needs to focus on recruiting a top striker this summer.
"Back in December, people were saying that we needed to bring in a goalscorer,"
"We were able to disguise that fairly well because over the next few months we were able to get goals from other positions, which was very important to us.
"We need to get some players here scoring double figures to give ourselves any chance at all. We don't have anybody in that category at the moment and that's something I will obviously be looking at."