Feyenoord Malacia was born in
Rotterdam and joined the
Feyenoord youth academy at the age of nine in 2008. He signed his first professional contract with them on 2 December 2015. He made his professional debut for Feyenoord in a 2–1
UEFA Champions League win against
Napoli on 6 December 2017, wherein he played the full 90 minutes. Malacia made his
Eredivisie debut for Feyenoord in a 1–1 tie with
Heerenveen on 13 December 2017. He was an unused substitute in the
2018 KNVB Cup Final, where Feyenoord beat
AZ 3–0. On 25 May 2022, he started in Feyenoord's 1–0
UEFA Europa Conference League Final loss against
Roma in Albania. He was later one of five Feyenoord players named in the competition's
Team of the Season.
Manchester United in a game against
Red Bull Salzburg in 2019 On 5 July 2022, Malacia signed a four-year contract with
Premier League club
Manchester United, with the option of a further year. United paid Feyenoord an initial fee of €15 million (£13 million), with an extra €2 million (£1.7 million) in add-ons, to make Malacia the club's first signing under manager
Erik ten Hag. Two days later, it was confirmed that he would wear the number 12 shirt last worn by
Chris Smalling. On 7 August, Malacia made his club debut as a substitute in a 2–1 home loss against
Brighton & Hove Albion in the Premier League. On 22 August 2022, Malacia started for the first time for United in a 2–1 win against
Liverpool. On 26 February 2023, he featured in the United squad to win the
EFL Cup final 2–0 against
Newcastle United, his first trophy with the club. Malacia started United's final
Premier League match of the
2022–23 season on 28 May 2023, which proved to be his last appearance for over a calendar year. He was an unused substitute during the
2023 FA Cup Final, which United lost to
Manchester City. In the summer of 2023, Malacia underwent knee surgery that kept him out of action for a year and a half. He made his long-awaited return to action on 12 November 2024 as part of
United Under-21s against
Huddersfield Town in the
EFL Trophy. He followed this up by making his first-team return sixteen days later, playing 45 minutes in the
Europa League against
Bodø/Glimt, for which he was praised by manager
Ruben Amorim. On 2 December, Malacia also started a Premier League game for the first time in over 18 months, playing the first half of a 2–0 defeat to
Arsenal.
Loan to PSV On 4 February 2025, Malacia joined
Eredivisie side
PSV Eindhoven on loan for the remainder of the 2024–25 season. He appeared in 12 matches across all competitions, and returned to Manchester United at the conclusion of the season.
Return to Manchester United In May 2025, after his loan expired, Manchester United put Malacia and several other players on the transfer list ahead of the 2025–26 season. However, Malacia was not sold before the closing of the transfer window, and was assigned to Manchester United's under-21 team. On 26 December 2025, Malacia made his first senior appearance for Manchester United since January as an 88th minute substitute in a 1–0 victory over
Newcastle United. ==International career==