Megson said, "I am delighted that we've managed to get him in. He's got a great deal of Premier League experience and is the type of player Wanderers supporters will like."
"He has a wholehearted approach to the game, is desperate to win and will be good in the dressing room.
"I signed Robbo for West Brom from Watford a good few years ago and I know him really well. He'll bring some competition down the left."