Aberdeen confirm signing of Celtic's Gary Mackay-Steven
The 26-year-old has put pen to paper on a two-year deal at Pittodrie.
Aberdeen have completed the signing of Celtic's Gary Mackay-Steven on a two-year deal.
He becomes Derek McInnes' fifth signing of the summer, following Greg Tansey, Greg Stewart, Nicky Maynard and Ryan Christie, for an unconfirmed fee of around £150,000.
The winger could make his debut in Aberdeen's second round Europa League qualifier at home to Bosnian side Siroki Brijeg on Thursday evening.
He can be registered in their European squad as a wildcard without another player having to drop out at his expense if it is processed before 11pm on Wednesday.
Mackay-Steven, who leaves with two years still remaining on his Parkhead deal, joined Celtic midway through the 2014/15 season from Dundee United.
He made 63 appearances for the club, scoring 10 goals and providing 11 assists.