Police are to investigate an incident which saw a ball boy kicked by Chelsea footballer Eden Hazard during his side's Capital One Cup semi-final against Swansea.

South Wales Police said they intended to interview the youth, who was seen to be kicked by the Belgian player after refusing to give him back the ball.

Hazard was sent off and Chelsea lost 2-0 on aggregate to send Swansea through to the cup final against Bradford at Wembley.

Chief Superintendent Josh Jones said: "South Wales Police is aware of the incident involving a ball boy at the Liberty Stadium in Swansea tonight. We are making arrangements for him to be interviewed. South Wales Police takes such matter extremely seriously."

Next month's Capital One Cup final will be Swansea's first major final in their 100-year history but the achievement was overshadowed by a moment of madness from Hazard. With just over 10 minutes remaining and Chelsea needing to score twice to take the tie to extra-time, he lost patience when a ball boy refused to hand over the ball after it had gone out of play for a goal-kick.

The ball boy fell to the ground as Hazard attempted to get the ball from him with the Blues forward then trying to kick it from under him but instead he appeared to make contact with the youngster. Several Chelsea players went to tend to the ball boy, who was left holding his ribs, before referee Chris Foy produced a red card.

After the game Chelsea manager Rafa Benitez said that Hazard and the ball boy had exchanged apologies in the dressing room after the match.

He said: "They apologised to each other. They both talked. The boy knows he was wasting time. Hazard was frustrated and trying to get the ball back. We can not change the situation. We are disappointed because we lost a player. The best thing for us is to move forward."

Swansea manager Michael Laudrup said he expected Hazard would regret the incident when he views it on television. He said: "I saw it from a very big distance from the bench. I've since seen it after the game. Hazard is a great player. When he sees the images I think he will regret it."

Laudrup denied the club had given the ball boys instructions to hold onto the ball when it went out of play. He said: "No, no. Definitely not. I think he was pushed and on top of the ball. I can understand all the frustrations when you are behind."