To describe this summer’s transfer window as frustrating would probably be an understatement if you are a Newcastle United fan - and many will look back at the last few months as a missed opportunity to strengthen, particularly in the defensive area.
From a Newcastle perspective it certainly wasn’t for the want of trying, and there were a total of four failed bids for England defender Marc Guehi, along with a late U-turn from Fulham star Tosin Adarabioyo earlier in the summer, with the 26-year-old ultimately choosing a move to Chelsea at the final moment.
As it stands, the Magpies currently have Fabian Schar, Dan Burn, Lloyd Kelly and Emil Krafth as their only centre back options until January when they will hope to welcome back Jamaal Lascelles and Sven Botman from injury. However, there is still a small window of opportunity for the Magpies to strengthen their squad with unattached players without a club.
With that in mind we take a look at nine of the best centre backs that are currently free agents. Would you like to see any of these at St James’ Park this season?
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1. Joel Matip
Last club: Liverpool | Getty Images

2. Mats Hummels
Last club: Borussia Dortmund | Getty Images

3. Sergio Ramos
Last club: Sevilla | Getty Images

4. Koffi Djidji
Last club: Torino | Getty Images
