article_snippet: Arsenal have put a new central defender on their summer shopping list, throwing Per Mertesacker's role at the club into doubt.
article_snippet: Gunners scouts have been instructed to identify potential central defensive targets this summer, despite the fact Gabriel only arrived from Villarreal in January.
article_snippet: Gabriel and Laurent Koscielny's place in Arsene Wenger's plans for next season look secure.
article_snippet: But the arrival of a new centre back in the summer is likely to have repercussions for Mertesacker.
article_snippet: Aleksandar Dragovic, pictured in action for Dynamo Kiev, has also been targeted by Arsenal .
article_snippet: And the arrival of a new centre-half could marginalise Mertesacker's role in Arsene Wenger's's plans.
article_snippet: The capture of a new central defender could also have consequences for Calum Chambers.
article_snippet: The England international has been used as cover at centre-back this season, but the club's transfer plans could mean Arsene Wenger's sees Arsene Wenger's long-term future at right-back or holding midfield.
highlights_snippet: Arsene Wenger has put a new defender at the top of Arsene Wenger shopping list .
  
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