Diego Simeone has refused to rule out Joao Felix leaving Atletico Madrid in the January transfer window.

The 22-year-old joined from Benfica in 2019 in a deal worth €126 million -- the second highest fee ever paid to sign a teenager -- but has failed to perform consistently since, or find a regular place in Simeone's starting team.

"I always understand everything, I'm open to everything," Simeone said in a news conference on Friday when asked if he would understand Joao Felix asking to depart.

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"The most important thing is the team. Joao is an important piece of our team."

The Portugal forward has started just three LaLiga games for Atletico this season, but impressed as a second-half substitute in their 2-0 derby defeat to Real Madrid last Sunday.

"He has to repeat performances like the one he gave the other day at the Bernabeu," Simeone said.

"He played 30-35 minutes and showed all the talent he has. Let's hope he repeats it, because that's the player we need."

Joao Felix's involvement this season has been limited. He underwent ankle surgery after playing in last summer's European Championships, returned in September, and then picked up a calf problem last month.

The return of Antoine Griezmann and signing of Matheus Cunha has also increased the competition for places in Atletico's forward line.

"I've spoken a lot with him. I don't have anything to explain to you about what needs to be worked on inside," Simeone added.

"Seeing Joao for just a few minutes, you realise he's a great player. He's going through a situation of growth, we've seen it with Portugal and maybe here too. It's about maturing and growing to find the consistency that football demands."

Atletico Madrid travel to Sevilla on Saturday with the hosts -- who are second behind leaders Real Madrid -- five points and two places above them in the LaLiga table.