Paul Pogba has admitted there is still a "question mark" over his Manchester United future but has promised to "give everything" while he remains at Old Trafford.

The Frenchman has been linked with moves to Real Madrid and Juventus after saying he wants "a new challenge" earlier this summer.

Sources have told ESPN FC that the 26-year-old will not be sold despite the European transfer window remaining open until Sept. 2.

But after starring for United during the 4-0 win over Chelsea on Sunday, Pogba left the door open for a move away.

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"I am always good whenever I play football," the midfielder told French reporters in the mixed zone. "It is what I love -- it is my job. I give the maximum each time I am on a green pitch.

"Obviously there have been things said, but only time will tell. This question mark remains.

"However, as I said, I am here in Manchester. I enjoy playing with my teammates and I always want to win every game. I always give it everything."

Focusing on Sunday's match, Pogba said that he was delighted with United's performance against rivals Chelsea and was effusive in his praise of new teammate Harry Maguire.

"I call him 'The Beast'," Pogba said. "Honestly, as you saw, he was really impressive. He is a leader. He fit right in with us in training. We talked about controlling the defence well and he has a good understanding with Victor [Lindelof]. It was a very good match to start with from the whole team.

"In the first half, we were dominated in terms of chances and possession, but we reacted in the second. Our changes enabled us to take over. We were better in possession and in terms of chances. We were lucky to have the lead through the penalty in the first half, but after a bad start, we finished the match well. We are satisfied with our performance."

Pogba was pivotal in setting up Manchester United's third and fourth goals against Chelsea -- laying on assists for Marcus Rashford and Daniel James -- and says that the squad is developing a good understanding within Ole Gunnar Solskjaer's system.

"That [position change] has been there for a while now -- since before this season," he said. "In terms of organisation, it is a bit more like how I play with the French national team. It does not bother me where I play, whether it is higher or lower, we adapt and enjoy. The team too, we were much better coming out of the back and that is something to keep going with in the coming games.

"Rashy and I understand each other well. We try to do a maximum number of passes like that. I am starting understand his calls for the ball too and that enables me to find him like I did."