Mexico striker Hirving Lozano is one of a number of players "being followed very closely" by Napoli, the club's coach Carlo Ancelotti has said.
Lozano, 23, has scored 11 goals in 18 games for PSV Eindhoven and could follow in the footsteps of Dries Mertens, who moved to Napoli from PSV in 2013.
The Serie A side are also interested in Villarreal midfielder Pablo Fornals, who has been linked with Arsenal, West Ham and Fulham.
"Fornals is one of the many players we're following, not the only one," Ancelotti told a news conference on Friday.
"He's on a list of players, which also includes Lozano, who are being followed very closely."
However, Ancelotti ruled out a move away for Allan this month after talks with Barcelona broke down. The Brazilian midfielder was also linked with Paris Saint-Germain.
"Allan's not been called up because he's had a testing week," Ancelotti said ahead of his side's trip to AC Milan on Saturday.
"We're going to keep him here to train and prepare himself for our game in the Coppa Italia on Tuesday.
"The only thing I know is that he's staying, fortunately, no more than that. He's an important player for us and he always will be. It's always been very clear with regard to Allan -- we don't need to sell him."
Ancelotti said Allan had expressed an interest in joining PSG, "but the player knew that he would only leave if the conditions were right for everybody, and he knows this was not the case."
Meanwhile, the manager added that midfielder Marko Rog could leave during the transfer window, saying: "We want to send him out on loan, but only if the conditions suit Napoli."