"We went to the wire with it," he admitted to the Birmingham Mail.
"We know all about him, and I have always admired him. Of course, I tried to get him before in the last Premier League transfer window we were in.
"Moving forward, we looked to bring in Michel. That fell down, but we noticed people like Tainio weren't featuring that much for Sunderland and I know you don't turn into a bad player overnight.
"He's an internationalist, very good with the ball and that's the type of player I want to bring to the club - and we're glad to be working with him at last."