William José Tesillo Gutiérrez (born 2 February 1990) is a Colombian professional footballer who plays as a centre-back for Atlético Nacional and the Colombia national team.

Tesillo scored his first goal in the top tier on 8 May 2011, netting his team's third in a 4–3 home success over Deportivo Pereira.

[5] He made his debut for the club the following 25 January, coming on as a late substitute for Luis Enrique Quiñones in a 3–2 win at Atlético Huila.

[7] He made his debut for the club on 31 January of the following year by playing the full 90 minutes in a 1–0 win at Boyacá Chicó.

[13] On June 28, 2019, his missed penalty kick in the shootout, saw Colombia eliminated by Chile in the 2019 Copa America quarterfinals.