The Germany international has not featured for the north London club since his clumsy tackle on Diego Costa led to his sending off against Chelsea last month.
Gabriel Paulista has started Arsenal’s last two games in the heart of the Gunners’ defence and has helped his team keep clean sheets against Southampton and Bournemouth.
Redknapp feels that Leicester City striker Jamie Vardy is likely to cause Arsenal’s defence significant problems with his pace during Sunday’s clash in north London, and suggested that Gabriel may be better suited to the job.
Redknapp wrote in his column for the Daily Mail: “Arsene Wenger has a big decision to make. That’s two clean sheets on the bounce without Per Mertesacker. He may be a leader, a World Cup winner and a big presence in the Arsenal defence, but on Sunday, they play Leicester.
“Mertesacker is experienced but one thing he is not is quick. When Arsenal travelled to Leicester they won 5-2, but the big German had a nightmare dealing with the raw speed of Jamie Vardy.
“After Leicester tore Manchester City apart, this has become one of the biggest games of the season. Over to you, Arsene…”
Arsenal head into Sunday’s game five points behind the Foxes in the table and in third place.
The north London side are looking to win the title for the first time since 2003-04.
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