CHELSEA captain John Terry has undergone a ‘precautionary scan’ on his right foot after taking a knock in training yesterday.

The news comes as a blow for Chelsea’s preparations as they attempt to win the double when they face Portsmouth in Saturday’s FA Cup final.

And if it proves to be a more serious problem, with a final assessment expected today, his participation in the World Cup could be in doubt.

A statement from the club said: “John Terry has today taken a knock in training and has gone to hospital for a precautionary scan on his right foot.

“He left Cobham walking freely in a protective boot, and we await the results which are expected on Thursday.”

It also gives England coach Fabio Capello a headache as he prepares for the World Cup in South Africa and the Italian will undoubtedly be monitoring the situation carefully.

Terry, stripped of the England captaincy following allegations about his private life this season, was named in Capello’s provisional 30-man World Cup squad alongside fellow centre halves Rio Ferdinand, Jamie Carragher, Michael Dawson, Ledley King and Matthew Upson.

Should the injury rule Terry out of the FA Cup final it would represent the latest in a line of pre-tournament injury scares for England.