Great Britain's Owen Miller claimed a shock 1500m gold after upsetting world and European champion Alexandr Rabotnitskii at the Olympic Stadium in Tokyo.
The 29-year-old Scotsman, who finished sixth at the 2019 World Championships, crossed the line in a winning time of 3:54.57.
Russian Paralympic Committee athlete Rabotnitskii and reigning Paralympic champion Michael Brannigan of the United States were expected to compete for top place on the podium in the T20 event.
Rabotnitskii came second in 3:55.78, with Italy's Ndiaga Dieng claiming bronze in 3:57.24, while Branningan's season's best time of 3:58.43 was not enough for a medal.
Miller's fellow Briton Hannah Taunton claimed bronze in the women's race with a personal best.
The 30-year-old – who incidentally hails from Taunton in Somerset – finished in 4:35.34, with Poland's Barbara Bieganowska-Zajac claiming the title for the third Games in succession, in a time of 4:27.84.
Ukraine's Liudmyla Danylina took silver, just under five seconds off the pace.
Meanwhile, Jonathan Broom-Edwards claimed gold for GB in the T64 high jump, his season's best of 2.10m the same height as the 33-year-old achieved in Rio where he only managed silver.
He said: "I am so emotional. To just get it right at the right time, I am so relieved, elated, excited and crying my eyes out.
"I've been striving for that gold for years. They were horrible conditions so I tried to keep my cool and get it right when it counted. And I am so proud of myself.
"(Silver medallist) Praveen (Kumar) pulled out a personal best and fair play to him, that put me on the back foot.
"I had to rise above that and I am so proud that I did. 2.10m was a bit of an ugly jump but it was a season best so I am delighted."
