The 18-year-old Brazilian centre-forward is being tracked by Real Madrid chief scout Juan Calafat, says AS.
On Sunday, he was involved as his team beat Internacional 3-2, head coach Luís Castro bringing him on for the final minutes as the Estrela Solitaria came from behind to win. Given his youth, he is yet to command a regular starting place, but he is steadily forcing his way into Castro's plans.
Were Matheus to join Madrid, he would initially play for the 'B' team, Real Madrid Castilla, a team coached by club legend Raúl.
As was also the case with his compatriots Vinícius, Rodrygo and Reinier, Matheus is a player who would need a period of adaptation in the Castilla squad.