Dujardin's bronze makes her the most decorated female British Olympian, with three gold, one silver and two bronze medals to her name.
In the early hours of Wednesday morning, Tom Dean and Duncan Scott, fresh from winning gold and silver respectively in the 200m freestyle, combined with James Guy and Matt Richards to win the 4x200m freestyle relay and GB's fifth gold of the Tokyo games.
The quartet finished just 0.03 seconds from breaking the world record after a strong swim from Guy helped Britain touch the wall three seconds clear of the second-placed Russian Olympic Committee team.
Britain's rowers earned a second place in the men's quadruple sculls but that proved the only medal of the day in the rowing races as the men's four finished fourth to end Team GB's run of golds - which stretches back over the previous five Olympics - in the event.
Britain's men's rugby sevens side lost out on a bronze medal after they were beaten 17-12 by Argentina in the third-place play-off. Fiji claimed gold in the event with a dominant display against New Zealand in the final.
Yorkshire's Jack Laugher was unable to defend his men's synchronised 3m springboard title as he and partner Dan Goodfellow finished seventh while Andy Murray and Joe Salisbury were knocked out of the tennis men's doubles. Britain sit sixth in the medal table with five gold, six silver and five bronze medals.