Liverpool’s bid to retain the title took a hit following a run of poor form that started after the festive period and they currently sit seventh on the Premier League, five points behind Chelsea who are in fourth position.
Merson believes the game is a crucial one for Jurgen Klopp’s men rather than the Gunners as he thinks Arsenal’s realistic chance of being in the Champions League next season is by winning the Europa League.
The 53-year-old believes the Reds cannot afford to lose more ground if they want to cement a place in the top four.
"If they are to have any chance, Jurgen Klopp's side need to win at the Emirates,” Merson wrote in his column for Sky Sports.
"I expect Chelsea to win at lunchtime on Saturday when they play West Brom at Stamford Bridge.
"If Liverpool don't win then, the gap will be too big, in my opinion. It could be as wide as eight points with eight games left to play.
"However, if Liverpool can beat Arsenal, it will be a massive win for them. All of a sudden, one of their harder games disappears and Chelsea have had one of their easier games as we reach the crucial part of the season."
