#3 Signing a young striker who could be used as a substitute
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Arsenal have been lacking a proper back-up striker in their line-up, who could be used as a substitute for either of their regular forwards. Denis Suarez has been signed from Barcelona recently, but he is not a typical striker and more of a winger rather.
Most of the big teams in the Premier League have a back-up striker in their squad; Liverpool have Daniel Sturridge, Chelsea have Olivier Giroud, Manchester United have Romelu Lukaku, and Manchester City have Gabriel Jesus, all of whom regularly come in as substitutes.
Arsenal would do well to sign a young striker, who can be used as a substitute to trouble the tiring opposition defenders with his fresh legs. Both Aubemeyang and Lacazette have performed reasonably well for the Gunners this season with 18 and 11 goals respectively, but they need a good back-up in big matches. For example, Arsenal could go for a young and energetic striker like Rodrigo of Valencia or Mauro Icardi of Inter Milan.