Portugal coach Roberto Martinez insists Joao Felix can be happy with his progress at Barcelona.
The striker is on-loan at Barca from Atletico Madrid.
Martinez told Sport: "He is 24 years old, he is a different player after his time in England. He understands the Premier very well, what is required of a foreign player, and when he arrived he had to become stronger.
"He is a player who has a great ability to protect the ball and there they made him even more consistent. Joo Flix is happy at Barcelona, very committed, he is a player who does not act like a player who is on loan, but with total commitment, and he shows me great maturity.
"I totally disagree (with his criticism). You can't blame a single player for how the team is doing. As a coach I value him a lot, his attitude and what he is doing. He had the opportunity to give up in a very, very difficult climate... I don't understand the scrutiny that is placed on him, it doesn't go with a 24-year-old player. He is a player who is on loan and who, in September and October, had a period of a very high level.
"He is on loan and this is not a stable situation. He has been decisive for Barcelona and, whenever he comes on, he scores goals or assists. He needs stability. Flix's time at Chelsea helped a lot with his training, but he needs a stable situation."