The Lille winger had made the Blues, Manchester City and Manchester United sweat on his signature, but his signing at Stamford Bridge should provide a further platform to build a squad capable of climbing up the table.
Roberto Di Matteo’s men might have won the Champions League and the FA Cup in the 2011-12 season, but the club’s league form was sub-par.
The Blues have already announced Marko Marin will join the ranks and their spending is not expected to end there.
Should Di Matteo - who is acting as Stamford Bridge’s interim manager at the moment - not be hired permanently then a new boss could herald a string of further arrivals.
Chelsea will hope Fernando Torres and his attacking team-mates can fill the shoes of outgoing icon Didier Drogba, whose final touch for the club will be forever remembered by the club’s supporters as the spot-kick which won them their first Champions League trophy.
HAVE YOUR SAY
Could Chelsea pull of a dramatic change in league form next season and beat the likes of Manchester City, Manchester United and Arsenal in the title race? Will they compete but not conquer? Is top four a more realistic aspiration?
Will Roman Abramovich’s side have to settle for Europa League qualification? Or could we witness a total fall from grace for the Blues which will culminate in the club finishing the campaign outside the top six?