As well as the Premier League duo, scouts from Bayern Munich and Barcelona are also expected to be in attendance at the Estádio José Alvalade.
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Manchester United and Chelsea are keeping tabs on Gelson Martins
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Gelson Martins has been likened to former Sporting Lisbon star Luis Figo
Martins has made 14 appearances so far this season - and also appeared twice for Portugal in World Cup qualifiers against the Faroe Islands and Latvia.
The 21-year-old's fine form has seen him likened to Portugal and Real Madrid legend Luis Figo.
United are keen to bolster their ranks after a difficult start to life under Jose Mourinho.
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Manchester United have previously raided Sporting Lisbon for Cristiano Ronaldo and Nani
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The Red Devils have raided Sporting in the past for wing wizards Cristiano Ronaldo and Nani.
And Chelsea, despite flying high at the Premier League summit, are also keen on January reinforcements.
Antonio Conte missed out on several high-profile targets in the summer but is eager to strengthen his squad ahead of a potential title push.