The agent of Sporting CP winger Gelson Martins admits enquiries are arriving ahead of the January market.

Gelson has been linked with Liverpool and Real Madrid this season.

Ulisses Santos told Sport: "Gelson is a player who has a lot of market interest, like Liga, Premier and Bundesliga, as a professional he must be ready for any decision, whether to leave or stay.

"He's a player of the Portuguese national team and wants to win championships. Portuguese clubs have a lower financial power and need to raise cash with sales or through television rights."