Francisco Andrés Sierralta Carvallo (born 6 May 1997) is a Chilean professional footballer who plays as defender for Championship club Watford.
Sierralta began his career with Universidad Católica and made his debut in the Chile Cup against Barnechea on 8 July 2015. He made his league debut on 26 September, replacing Marco Medel in the final minutes against Huachipato.
On August 2017, Sierralta joined Udinese and was loaned to Parma. Sierralta's loan was extended for another year on 7 August 2018, having achieved promotion to Serie A during his first year with the club.
On 11 January 2020, Sierralta joined Serie B club Empoli on loan until 30 June 2020.
On 9 September 2020, Sierralta joined Championship club Watford on a three-year contract.
5 appearances in the current 2022-2023 Season