The versatile 20-year-old joins until April 22, giving Clarke cover at centre-back, left-back and defensive midfield.

Ake has played 11 times for Chelsea's first team and was an unused substitute in the Capital One Cup final against Tottenham last month.

The Netherlands U21 international covers exactly the same positions as Nathaniel Chalobah, which suggests Chalobah's injury picked up in the FA Cup quarter-final with Bradford could be worse than first feared.

Ake will train with his teammates tomorrow but he won't be able to force his way into Clarke's FA Cup semi-final plans due to being cup tied after a brief appearance for Chelsea in this season's competition.

Clarke said: "I’m delighted to add a player of Nathan’s quality to our first team squad at this important time of the season.

"He has been a fixture in Chelsea's first team squad this season and we are grateful that Chelsea have allowed him to join us here at Reading to get some competitive minutes on the pitch.

"He is a very talented player who I have been aware of for some time and I look forward to working with Nathan in the coming weeks."