Manchester United are reportedly keeping a close eye on Joao Felix's situation at Atletico Madrid, with the attacker said to be increasingly frustrated at Wanda Metropolitano.
The 22-year-old has failed to find the back of the net for Diego Simeone's side this season, only providing three assists in 11 appearances in all competitions.
Felix's struggles in front of goal have seen him lose his spot in the starting XI, and he was an unused substitute against Club Brugge in the Champions League last week despite Atletico needing a goal.
The Portugal international has played just 19 minutes of football in his side's last two league games, meanwhile, and the situation is believed to have created friction.
According to Marca, Felix's relationship with Simeone is at an all-time low following the manager's failure to use him in the Champions League contest with Brugge.
The report claims that the Portuguese 'cannot stand' his current situation and recently met with his agent Jorge Mendes to discuss a possible exit.
Man United, according to A Bola, are 'attentive to the situation', with the Red Devils said to be long-term admirers of the forward.
The report claims that Liverpool, Manchester City, Bayern Munich and Barcelona have also asked to be kept informed of any developments surrounding his future.
Felix moved to Atletico in a big-money move from Benfica in July 2019, and he has represented the Spanish giants on 122 occasions in all competitions, scoring 29 goals and contributing 18 assists.
There was speculation surrounding the attacker's future over the summer, but Atletico are believed to have made it clear that he would not be for sale under any circumstances.
Man United are likely to be in the market for a new centre-forward next summer, with Cristiano Ronaldo expected to leave Old Trafford on a free transfer.
Marcus Rashford and Anthony Martial have both impressed this season, but Ronaldo's departure would leave the 20-time English champions short of options heading into the 2023-24 campaign.
Man United were linked with Felix in the latter stages of his time with Benfica and are also believed to have contacted Atletico during the recent window for an update on his situation.
There is believed to be a €350m (£304.6m) release clause in the forward's contract at Wanda Metropolitano, placing the La Liga outfit in a strong position to demand a high transfer fee.
