Marcelo Allende

Allende started his youth career at Cobreloa. After Chile's participation in the U-17 World Cup, he caught the interest of Colo-Colo and Universidad de Chile for his signature, although neither move materialized. In 2016, the player transferred to Deportes Santa Cruz of the Segunda División de Chile in order to gain more playing time, making his debut against Naval. In his second season at the team, he scored his first senior goal against Melipilla, and became a regular starter, finishing the campaign with four goals. Allende had a two-month trial with English club Arsenal, featuring for their under-19 team at the Durban International Cup. The team won the competition, and the player was invited to further trials with the club. In April 2017, following a third trial, the English tabloid press reported that Arsenal had offered Allende a professional contract.

Necaxa

With this being so on 7 September 2017 Allende signed up with Mexican side Necaxa, with the intention of rejoining the club in 2018 while remaining on loan with Santa Cruz.

Mamelodi Sundowns

On 24 August 2022, Allende was announced as new player of South African club Mamelodi Sundowns and made his debut in the same day scoring a goal versus Stellebosch.

On 15 June 2015, Allende made his debut for Chile U-17 in a friendly defeat against Paraguay. He was later selected on the list of players that would take part in the tournament, held on home soil. He was a starter on Chile's four matches at the U-17 World Cup, netting against Nigeria and the United States. On 16 October 2016, Allende made his debut for the Chile U-20 in a friendly win against Paraguay U-20 adding another cap against Ecuador U-20, but was ultimately left out of the final squad for the 2017 South American Youth Football Championship. He scored his first goal for the U20's on 10 August 2017, in a friendly win against Japan. At under-20 level, Allende represented Chile in both the 2018 South American Games, winning the gold medal, and the 2019 South American Championship. Allende made his debut for Chile national team on 11 December 2021 in a 1–0 win over El Salvador.

Arsenal

Durban International Cup: 2016 Necaxa

Copa MX: Clausura 2018 Supercopa MX: 2018 Mamelodi Sundowns

South African Premiership:2022–23;2023–24 2026 CAF CHAMPIONS LEAGUE Chile U20 South American Games Gold medal: 2018 CAF Champions League: 2025–26 Individual

Uruguayan Primera División Team of the Year: 2020