The 22-year-old ?6million-rated Turkey player has failed to agree terms on a new contract and is available for a knockdown fee.
Target: Dortmund's Nuri Sahin (left)
However, Villa will face strong competition from Real Madrid, Chelsea and Liverpool.
The Midlander: Houllier's heart scare just the latest in a long list of dramasWe won't see the best of Ireland until he's fit, says Villa caretaker McAllister
Explore more:Places: Liverpool, Chelsea