Paul Hartley believes Celtic midfielder Aiden McGeady has the class to unlock Shakhtar Donetsk's defence this week.

"Aiden has been terrific for the last six weeks or so and has gone out and won games for us on his own. I knew he was good before I came here but I think you're seeing the best of him this season. He's an exceptional talent who can go all the way to the top."

Manager Gordon Strachan, who expects Shakhtar to come and attack, believes that the credit for the sheer incline in the graph of McGeady's progress belongs to the player himself.

"You become more confident the better you become physically," he said. "When you don't get tired you don't make mistakes and when you take them away your confidence flows. Sometimes Aiden used to try too hard and then get down on himself when something miraculous didn't happen. I think his game has also got simpler but better. Plus he has incredible pace."