Chelsea footballer Eden Hazard was sent off after he kicked a ball boy who had refused to return the ball near the end of a Capital One Cup semi final.
The ball boy had refused to return the ball, lying on it to stop the Belgian star resuming play.
Hazard then lost his cool and tried to kick the ball from underneath the ball boy but in the process caught him in the ribs.
Referee Chris Foy called him across and gave him his marching orders, effectively ending the visitors' hopes of securing a route back into the tie.
"Demba Ba told me the ball boy held onto it but I saw him kick him and you can't do that to a young boy," Swansea captain Ashley Williams told Sky Sports.
The game finished goalless on the night and 2-0 to Swansea on aggregate.
The Welsh side face Bradford City in the competition's Wembley final.