The Spanish giants are keeping tabs on Koscielny.
Arsenal face a struggle to keep hold of their best players this summer as Real Madrid look to make a move for centre-back Laurent Koscielny, according to AS.
The Frenchman has been greatly impressing at the Emirates Stadium over the past season and Los Blancos want to bring in the 28-year-old to shore up their defence.
They will face a tough challenge though as Gunners boss Arsene Wenger views Koscielny as one of his most important players and will do all he can to keep hold of the defender.
Madrid have leaked more goals this term then their La Liga title rivals Atletico Madrid and Barcelona and head coach Carlo Ancelotti is keen to address that in the summer.
There are question marks over the defensive capabilities of both Pepe and Sergio Ramos and Ancelotti views Koscielny as the ideal candidate to help resolve that.
This term the France international has proven his form at the back alongside Per Mertesacker and the duo are among the best partnerships in the Premier League.
Koscielny has been in north London since 2010 after completing a £10m transfer from FC Lorient and since then has played 163 matches for the club in all competitions.
His form has seen captain Thomas Vermaelen become a peripheral figure at the Emirates and the Belgian is likely to be sold in the summer a result.
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