Swansea City midfielder Jonathan de Guzman has claimed that his side used the frustration of Manchester United supporters to their advantage on Sunday.
The Swans became the fourth away team to win at Old Trafford in six games when they secured a 2-1 victory to knock the Red Devils out of the FA Cup.
De Guzman thinks that Wilfried Bony's last-minute winner came as a result of the belief that Swansea gained from the edginess of United's home fans.
"You could tell their fans weren't pleased when they played the ball backwards and we used that to our advantage," De Guzman told reporters.
"You could feel it. The fans wanted to win. They are at home. Their crowd is an extra man. But if they are turning their backs or things are not going well and the team is not playing the way they should, as an opposition player you have to use that.
"You could hear the fans booing at the end of the game and when they played the ball backwards. We knew that as well."
Ten teams, including Hull City and Stoke City, have better home records than United in the Premier League this season.