Nicolás Hernán Siri Cagno (born 17 April 2004) is a Uruguayan professional footballer who plays as a forward for Belgian Challenger Pro League club Lommel, on loan from Montevideo City Torque.

[3][4] On 19 March 2021, he scored a hat-trick in a 5–1 league win against the same opponent, at the age of 16 years and 348 days in the Uruguayan first division.

This made him not only the third youngest player in history to score a hat-trick in professional football, only behind Pelé and Trevor Francis,[5] but also the youngest-ever player to score a treble in the top flight, since Pelé did it in a friendly and Francis in the English second tier.

[6] He also became the youngest South American to score a hat-trick in professional football, breaking the previous record set by Ronaldo in 1993.

[9] On 27 January 2025, Siri joined Belgian club Lommel on a loan deal until the end of the season.