[8] After the 2019 Rugby World Cup, where de Allende was a member of the victorious South African team, he joined Japanese Top League side Saitama Wild Knights.

Though de Allende's two-year contract didn't officially commence until 1 July 2020, he arrived in Ireland in May 2020 after the cancellation of the remainder of the 2019–20 Top League and completed two weeks of isolation due to the COVID-19 pandemic.

[9][10] De Allende made his debut for Munster in their 27–25 defeat against Leinster on 22 August 2020,[11] and scored his first try for the province in their 52–3 win against Italian side Zebre in round 8 of the 2020–21 Pro14 on 30 November 2020.

[12] He made his Champions Cup debut for the province in their opening fixture of the 2020–21 competition against English side Harlequins on 13 December 2020, starting in Munster's 21–7 home win.

[16] In May 2014, De Allende was one of eight uncapped players that were called up to a Springbok training camp prior to the 2014 mid-year rugby union tests.

[22] He scored two tries in the game, earning praise from the World XV and former Australia coach Robbie Deans, who commented that "Damian has been playing remarkable rugby the whole year and he keeps doing the right things.