The Gunners have been tipped by many to be the favourites to win the top-flight crown this term after their impressive start to the season.
Arsenal have already beaten the likes of Manchester City and Manchester United in recent months to mount a serious bid for their first title since 2004.
However, injuries to the likes of Francis Coquelin and Santi Cazorla have left the north London side short of options in midfield.
And former Gunner Merson feels that Arsene Wenger will need to sign a holding midfielder as cover for Coquelin in the new year if Arsenal are to sustain a genuine title challenge.
Merson wrote in his column for the Daily Star: “I still think they need a holding midfielder in January though.
“Mathieu Flamini did OK against Manchester City but if he has to play 15 games they are not winning the league.”
Arsenal face Barcelona in the last 16 of the Champions League next year.
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