The 30-year old midfielder has joined the relegated R’s for a fee of around £1million and manager Harry Redknapp was thrilled to bring in such a player to add to the already experienced additions of Danny Simpson and Richard Dunne.
"We're trying to change the club around a bit," Redknapp told the club's official website.
"Karl's another piece of the jigsaw that can hopefully help us build a team that can challenge for promotion.
"He's a combative midfielder and you know what you're going to get from him week in, week out. He'll be ready for the Saturday, Tuesday slogs and you know you can rely on him.
"Like Danny Simpson and Richard Dunne, he's been promoted to the Premier League before so he knows what's needed."