The Villa boss admitted he thought the 24-year-old striker would opt for the £18k a week deal the Bhoys had tabled - but when it became clear he was stalling on his future, he decided to swoop. The Scottish international is now expected to make his debut in Saturday's home Barclays Premiership clash against West Ham, after signing a three-and-a-half year deal worth around £25k per week. "Shaun was out of contract in the summer, and we left it late before we even went in for him because I honestly thought he would sign a new contract at Celtic," said O'Neill. "Shaun is an excellent player, and I think he is as conscientious as they come. He will be a big asset to this club, I have no doubts about that."