Dries Mertens is tightlipped over his future at Napoli.

The Belgium striker was again watched by Manchester United in victory at Inter Milan.

He said: "Of course I am concerned with the future, but for now I can not say anything about it, we'll see."

Mertens also remarked: "We play very good football and makes it seem as if the opponent is not as fit. That's probably not the case, but because we always have the ball and play at a higher tempo opponents have to constantly chase us.

"That's tiring and therefore there seems a big difference in fitness. The fact we can play like this is especially thanks to our Coach Maurizio Sarri."