Juan Manuel San Martín Da Costa (born 20 January 1994) is a Uruguayan professional footballer who plays as a forward for Portuguese club Real SC.

Born in Rivera, San Martín is a product of Peñarol youth system, joining them in 2009, at age 15.

Two years later, reports in the press informed that he, Jim Varela and Elbio Álvarez were joining S.L.

At the end of the loan, he returned to Benfica B. San Martín was part of the squad of the Uruguay U-17 that took part in the 2011 South American U17 in Ecuador and in the 2011 FIFA U-17 World Cup, playing five matches and scoring once.

This biographical article about a football forward from Uruguay born in the 1990s is a stub.