As reported by the BBC, Gyokeres has received approval from Sporting to head to London for his medical now that the final deal negotiations have concluded.
A transfer fee of £63.5 million has been agreed upon by both parties, although discussions had recently stalled due to disputes over sell-on fees.
However, the 27-year-old will soon be able to sign what is expected to be a five-year contract in the coming days.
After missing out on Gyokeres' fellow countryman Alexander Isak and reportedly showing interest in Benjamin Sesko, the Gunners have shifted their focus to Gyokeres to occupy the center-forward role that has been open at the Emirates for quite some time.
Arsenal manager Mikel Arteta is understandably eager to involve the former Coventry City player in his squad's pre-season preparations, "Clearly, once we have finalized everything with the player, we want to integrate him into the team as swiftly as possible," he stated.
The Swedish international, who scored 54 goals in 52 appearances for the Portuguese team last season, has been linked with many of Europe's top clubs over the past year.
He will soon join his new teammates on their tour of Asia - currently, Arsenal is in Singapore and will then head to Hong Kong to face rivals Tottenham Hotspur later this month.