The Swansea City defender believes that the change of manager this week – forced on them when Gary Speed was appointed as manager of Wales – means that they could be a different proposition than the one they would have been had Speed still been in charge.
“It’s the worst time to play against them,” Williams told BBC Sport Wales.
“Everyone knows that when you lose a manager or get a new manager it brings the squad together and they dig deep and try to impress people.”
Williams will be looking to help the Swans extend their unbeaten away run to seven games with victory at Bramall Lane inย contrast to their home form which has been stuttering recently
“I think it’s down to the way the opposition has been playing,” he said. “When we play away and they are at home, they try and win the game which suits us a little bit more.
“Us at home, a lot of times they come to not lose which makes for a dull game so we work a bit harder at home trying to do what we do and we want to try and keep the run going away from home.”
Williams will line up against former Swan Leon Britton who joined the Blades in the summer “It will be funny to see him in a different kit,” added Williams.
“He’s a great lad, but at the end of the day this is business and we’ll be going there to get the win and have a laugh afterwards although I’m sure there’ll be a bit of banter during the game.”