The 20-year-old joined Sam Allardyce's side in August on an initial
deal until January and will now remain at Ewood Park until the
conclusion of the campaign.
Di Santo has made 15 Premier League appearances for Rovers,
but has contributed just one goal to date in the victory over local
rivals Burnley.
Blues boss Carlo Ancelotti will be without strikers Didier
Drogba and Salomon Kalou during January due to the African Cup of
Nations, but has decided against recalling the Argentinian forward.
Di Santo will now hope to help Rovers improve their
disappointing goals tally, with Allardyce's troops averaging just
one goal a game.
Blackburn, who have not won in their last six matches, are
just three points above the Premier League relegation places.
A statement on Chelsea's official website read: "Franco Di
Santo's loan spell at Blackburn Rovers has been extended until the
end of the season."
