Britain's Paul Blake retained his T36 800m title at the IPC Athletics World Championships.
The GB team captain, who had won silver in the 400m on Friday, took the lead after 200m on a hot, humid night in Doha and was never headed after that.
Blake, 25, who has cerebral palsy, held off fast-finishing Russian Artem Arefyev to win GB's seventh gold of the championships by 0.24 seconds.
"I felt a huge sense of relief crossing the finish line," he told BBC Sport.
|Baroness Tanni Grey-Thompson, 11-time Paralympic champion|
|"It's really nice to see someone run from the front. Paul looked very cool and calm and ran a smart, lovely race but with 50m to go I thought he was going to get caught.|
|"These muggy conditions are very challenging for athletes with cerebral palsy so for him to run a season's best is very impressive."|
"I'm so pleased to defend my title. I've worked very hard all season and I knew what I needed to do here but it was a matter of doing it on the day and thankfully I did it.
"It was pretty tough - my aim was to go out in 63 seconds, I did that and I hoped to carry that on to the next lap.
"I was a little bit slower on the second lap, but that doesn't matter because I wasn't bothered about the time. I was more concerned about winning.
"This is a great confidence boost for me with the Rio Paralympics coming up next year."
Medal table (top 10)
Wheelchair athlete David Weir's hopes of his first Doha gold in the T54 5,000m were ended when he could only finish seventh in the final.
Thailand's Rawat Tana, who beat Weir to gold in the 1500m, took another title ahead of Switzerland's Marcel Hug.
Weir had been in contention until the final lap but found himself just too far back to mount a challenge in the last 400m.
"I should have stuck on Rawat's wheel for the whole of the race because it seemed like he was the strongest man in the field," he said.
"When you are two or three chair lengths back with a lap to go, you aren't going to close it down.
"I felt I had the ability but I just wasn't in the right position when it came to the final lap.
"This shows that this class is not just about me and Marcel anymore. That gets a bit annoying, because it hasn't been like that for years. The whole field is strong and everyone is beatable on their day. It just depends who gets the best position and who is stronger on the day and Rawat was stronger today."
But the athlete, nicknamed the Weirwolf, said such a disappointing result has not affected his determination to continue on to next year's Rio Games.
"I will be back and fighting fit for the start of next season," he insisted. "I can't win everything but I will bounce back and win another big race."