David Weir kept the Olympic Stadium crowd believing a golden quadruple could be on the cards with another imperious ride.
The wheelchair racer, back on the track less than 13 hours after winning his second title of London 2012, cruised into the final of the T54 800 metres.
The 33-year-old, already the 5,000m and 1500m champion, was content to sit behind Swiss rival Marcel Hug for the first lap, but, when Australia's Kurt Fearnley also came up to challenge, moved into the lead with 350m to go and then hit the turbo charge to roar away from the field.
The Londoner had plenty of time to ease down before he crossed in the line in one minute 37.09 seconds, more than a second clear of Hug.
Weir told Channel 4: "I had to keep remembering that there are two slots (to qualify) not three.
"I was a bit tired this morning but I got through.
"I got a bit more sleep than the first night (after his first gold medal). I just need to eat a bit more food tonight and I should be alright for the final."