After losing interest in Benjamin Sesko from RB Leipzig, Arsenal is now focusing on signing Gyokeres, a Swedish centre-forward.
Berta arrived in Lisbon the day before yesterday for face-to-face talks with Sporting's directors to discuss the transfer fee.
It is reported that Berta is aiming to reach an agreement on a fee that could potentially rise to £70 million with Sporting.
Earlier this year, Gyokeres agreed to join Arsenal on a lucrative deal worth £200,000 per week.
During his time at Sporting last season, Gyokeres impressed with an impressive 54 goals scored.
