Nyorera kupfuurira kweiyi ndima - Kumitambo yeOlympic yeTokyo ya2020, Duncan akahwina sirivheri mumamita mazana maviri akasununguka, achipedza 0.04 masekondi kumashure kwemukundi uye waanotamba naye, Tom Dean. Akatevera nendarama sechikamu che4 × 200m freestyle relay team naTom Dean, James Guy, naMatt Richards, vachirihwina muEuropean rekodhi yemaminitsi matanhatu nemasekondi makumi mashanu nemashanu nemashanu. Akatorawo sirivha mumakwikwi evarume emamita 200 ega ega, uye imwezve mumakwikwi e4 × 100 metres.
naLuke Greenbank, Adam Peaty, naJames Guy, vachimuita mutambi wokutanga weBritain kukunda menduru ina muMitambo imwe chete zvichitungamirira kunzi akasarudzirwe kuva knighthood.