Boulahrouz has fallen out of favour at Stamford Bridge

Holland international Boulahrouz, 25, joined Chelsea last summer for around �7m but fell out of favour and has played only four times since January.

Uefa Cup holders Sevilla are among the clubs interested in signing him.

"Discussions are ongoing with several clubs," read a statement from Chelsea's official website.

The doctors recommended that I also wear it next season Chelsea goalkeeper Petr Cech on his protective head guard

Boulahrouz was expected to provide cover across the Chelsea defence but boss Jose Mourinho often fielded the likes of Geremi or Lassana Diarra, both midfielders by trade, at right-back.

Glen Johnson has also returned from last season's loan spell at Portsmouth to bolster numbers, Tal Ben Haim has also arrived and Alex may be available after a loan spell at PSV Eindhoven, if his work permit problems are resolved.

Boulahrouz has not travelled with the Blues squad for the pre-season tour of the United States.

Meanwhile, goalkeeper Petr Cech is set to continue wearing the protective head guard he used when he returned to action last season after fracturing his skull against Reading.

Cech told Czech newspaper Sport: "The doctors recommended that I also wear it next season.

"It would be better if they said that I could take it off but on the other hand there is no sense in risking it. I have no problem with it, I got used to it very quickly."