The north London side are leading the race to finish in third place in the Premier League table ahead of their trip to Manchester United on Sunday.
Up front, when Olivier Giroud got injured Arsenal’s season kind of went with him, so they need another forward in case that happens again
Arsenal, who crashed out of the Champions League at last-16 stage, are set to defend their FA Cup crown against rivals Aston Villa at Wembley later this month.
But former Gunners playmaker Merson believes Wenger needs to sign a new spine for his Arsenal side if the north Londoners are going to challenge for silverware next season.
“They definitely need a new goalkeeper,” Merson told Sky Sports. “If you look at their two goalkeepers, when have they saved them points over the course of the season? I can’t remember many times.
“Look at how many points David de Gea has saved for Manchester United, and Thibaut Courtois for Chelsea. They soon mount up the points.
“At centre-back, Gabriel Paulista could be pretty good next season but they still need another centre-half and they also need a holding midfield player, but I don’t know who they’ll go for.
“You could say Morgan Schneiderlin, but at the same time a lot of Southampton players went to Liverpool last year and not many of them have cut it.
“Likewise, if you’re going to Arsenal from Southampton it’s a big, big move, so maybe they need someone who’s already played at that pressure level. I do like Schneiderlin, though.
“And up front, when Olivier Giroud got injured Arsenal’s season kind of went with him, so they need another forward in case that happens again.”
Merson added: “I’ve just gone through the whole spine of the team. Every team has to have a good spine to win anything and I think they need new faces in every position down the centre – that’s worrying.”
Arsenal have been linked with a move for out-of-favour Chelsea goalkeeper Petr Cech and Real Madrid captain Iker Casillas in recent weeks.
The Gunners boss is also believed to be an admirer of Monaco midfielder Geoffrey Kondogbia and Southampton star Morgan Schneiderlin.
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