Former Celtic forward Kris Commons on BBC Radio Scotland's Sportsound
"He would be a good addition because Celtic have been crying out for a good centre-half.
He's not had a great deal of football - four international caps - so at the minute he's one for the future. In 12-18 months you'll probably see the best of him. He's on a long-term deal as well so he's in no rush.
Celtic aren't going to pay £8m, £9m, £10m for a centre-half that's 21 and was playing on loan at Ayr United just over a year ago. He got his experience in the lower leagues but this is a guy that's only played 30-plus games for Aberdeen. He's not played 300 games in competitive football."
And the above makes it crystal clear why McKenna will not end up at Celtic.