Having worked with the Scot from January 2011 until June 2012, Agger isn't shocked by the impact he's had.
"It doesn't surprise me," he admitted to liverpoolfc.com. "When Steve was here, he was quality - he's one of the best people I've worked with. He's a clever coach and I don't have enough good words to say about him.
"He was good for me because he sees the game the way I see it. We were quite similar.
"I wish him all the best...but not on Saturday, of course."
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