Celtic manager Martin O'Neill has been talking to the media before Monday's Scottish Premiership opener against Dundee. O'Neill confirms West Ham have bid for midfielder Arne Engels, although it "doesn't remotely meet our valuation". O'Neill stressed Celtic's aim is to try to keep both players and said it would be a "difficult task" to replace them, "but it's difficult to stop people if their ambition is to play in a big, big league".