The Gunners were keen to sign a new striker in the January transfer window, but the market ultimately passed by without any new additions due to concerns over their Financial Fair Play situation.
However, Arsenal are expected to make signing a new number nine one of their main priorities for the summer transfer window.
Arsenal's current first-choice forward Gabriel Jesus continues to be hampered by injuries, while his fellow striker Eddie Nketiah has been unable to nail down a regular spot in Mikel Arteta's starting lineup.
With the Gunners in the market for reinforcements, a recent report suggested that Gyokeres features on a four-man striker shortlist.
According to The Mirror, Arsenal scouts were in attendance to watch Gyokeres and his teammate Diomande in Thursday's Taca da Portugal clash with Benfica.
The Arsenal officials saw Gyokeres score the second goal in a 2-1 victory to give Sporting a narrow advantage after their first leg of the semi final.
The Sweden international continued his red-hot form with another strike in Sunday's 3-2 home win over Farense in the Primeira Liga.
As a result, the Gyokeres has now scored a total of 32 goals in 35 competitive appearances since arriving from Coventry City last summer.
The 25-year-old is believed to have a £86m release clause in his Sporting contract which runs until the summer of 2028.
Arsenal were also believed to be watching centre-back Diomande, who played the duration of Thursday's cup win over Benfica.
Diomande has featured in 25 matches across all competitions this season, and he was also part of the Ivory Coast squad that won the Africa Cup of Nations in January.
The 20-year-old, who joined Sporting from Midtjylland in 2023, has over three years left to run on his current deal with the Portuguese giants.
Like Arsenal, Chelsea were said to be monitoring both Gyokeres and Diomande at the Estadio Jose Alvalade on Thursday.
Paris Saint-Germain and AC Milan also had scouts in attendance, while officials from Manchester United were understood to be keeping a close eye on Benfica duo Joao Neves and Antonio Silva.