Elias led Shakhtar to a 5-1 win over Kudrivka in Lviv on Monday, scoring with a header and finishes off both feet in the second half to earn player of the match, in what was his first appearance of the new Ukrainian Premier League season.
Scouts from both Premier League clubs were present in the stands, with AC Milan and Porto also said to be monitoring the 20-year-old, and an official bid is expected soon with Shakhtar valuing him at around £30m, reports The Sun.
The Brazilian, who joined Shakhtar from a boyhood club in Brazil for around €17m roughly 18 months ago, has all the traits scouts look for in a modern No.9: comfortable off either foot, a genuine threat in the air, and composed when chances fall to him inside the box.
Reports sent back from both clubs pointed to his technical quality and calm finishing as the standout features separating him from rival young forwards on their radar.
With Mikel Arteta keen to bolster his forward options and find a lasting answer at centre-forward as Arsenal defend their Premier League title, the Gunners are said to have had eyes on Elias for weeks before Monday's display tipped the scales toward a more serious pursuit; his comfort playing with his back to goal, combined with the ability to make runs beyond defenders, is viewed internally as a natural fit for Arteta's system.
Manchester United, meanwhile, are assessing their own forward options amid uncertainty over Joshua Zirkzee's future, with reports suggesting interest from Serie A in the Dutch forward, and see Elias's two-footed finishing and physical presence as well matched to their high-press, quick-transition approach under the current coaching staff.
Both clubs are capable of meeting Shakhtar's asking price, though they face stiff competition from Milan and Porto, who have also delivered positive scouting reports of their own.