The Gunners have prioritized Gyokeres' signing after losing interest in RB Leipzig's Benjamin Sesko.
Berta arrived in Lisbon the day before yesterday to meet with Sporting's directors and discuss the terms of the transfer, including the fee for Gyokeres.
It is believed that Berta is hoping to negotiate a deal worth up to £70 million for the Swedish centre-forward.
Earlier this year, Gyokeres agreed to join Arsenal on a lucrative contract worth £200,000 per week, following an impressive season with Sporting where he scored an impressive 54 goals.
