Arsenal's Mertesacker a doubt for Chelsea encounter

Arsenal are in danger of being without one of their defensive anchors for Sunday's critical match against league-leading Chelsea.

An ankle injury could keep central defender Per Mertesacker out of the weekend affair if he's unable to return to full training in time.

Mertesacker's progress in training will be the focus for the Arsenal staff in determining his status for Sunday's match.

The German international sustained the injury during Arsenal's FA Cup semifinal win over Reading, and manager Arsene Wenger is likely preparing for the match against Chelsea as though Mertesacker will be absent, according to The Telegraph.

Gabriel Paulista looks set to fill in for Mertesacker at the back. 

Paulista has only managed to play in five league matches since making the move to London from Villarreal, and could be asked to contain a Chelsea attack that's scored the second-most goals thus far.