Guillermo Varela Olivera ([ɡiˈʝeɾmo βaˈɾela oliˈβeɾa]; born 24 March 1993) is a Uruguayan professional footballer who plays as a right-back for Campeonato Brasileiro Série A club Flamengo and the Uruguay national team.

Varela won two Uruguayan Primera División titles with Peñarol, before returning to Europe in January 2019 when he signed for Danish club Copenhagen.

[8] He made 33 appearances and scored once, when he was set up by Martin Ødegaard in a 4–0 win over Barakaldo on 21 February 2015, at the Estadio Alfredo Di Stéfano in that season's Segunda División B.

[10] He made his debut on 5 December 2015, as a half-time substitute for Paddy McNair in a goalless Premier League draw against West Ham United at Old Trafford.

On 25 February 2016, in a Europa League Round of 32 return leg against FC Midtjylland, he assisted on the second of the two goals Marcus Rashford scored on his senior debut.

[18] On 20 December 2018, Danish Superliga team FC Copenhagen announced that Varela would join them in January 2019, on a deal until June 2023.

[23] On 12 January 2023, Flamengo announced that Varela had signed a pre-contract for a permanent deal starting at the end of his contract with Dynamo Moscow on 1 July 2023.

[28] On 5 March 2016, following his emergence into the Manchester United first-team, Varela received his first call-up to the Uruguay senior squad, for the World Cup qualifiers against Brazil and Peru later that same month.