Northern Ireland's Rhys McClenaghan secured a surprise pommel horse gold medal and Cypriot Marios Georgiou twisted his way to the floor title as double Olympic champion Max Whitlock was beaten on both of his preferred apparatus on a day of gymnastics shocks at Gold Coast 2018.
McClenaghan showed his strong performance in qualifying was no fluke as he beat Whitlock by virtue of a higher execution score to seal his country's first medal of any colour at the Commonwealth Games here.
The triumph for the 18-year-old Northern Irishman came after Georgiou followed his bronze medal in the all-around with a superb floor routine which proved too good for Whitlock.
Courtney Tulloch and Georgia-Mae Fenton restored English pride following Whitlock's disappointment by claiming gold in the rings and uneven bars respectively.
Shallon Olsen clinched her second crown of the Games as she added the vault title to the gold medal she won as part of the victorious Canadian team.
Whitlock came into the two finals as the overwhelming favourite after he topped the podium in both the floor and pommel horse events at the 2016 Olympic Games in Rio de Janeiro.
The 23-year-old, one of the household names competing at the Games here, was unable to relive those glory days as he suffered two shock defeats in quick succession.
Georgiou laid down a marker when he scored 13.933 on the floor, although the total was comfortably lower than Whitlock's best.
But the English star made several uncharacteristic mistakes during an inconsistent routine and eventually languished down in sixth place.
The triumph for Georgiou saw him become just the third Cypriot gymnast to win a Commonwealth Games artistic gymnastics title.
Canada's Scott Morgan was the recipient of the silver medal after his display yielded a total of 13.833, while bronze went to Scotland's Daniel Purvis, who was a point further adrift in third.
Worse was to come for Whitlock, however, as he failed to defend his pommel horse crown.
The reigning world champion on the apparatus was considered a shoo-in for the gold but knew he would face a tough challenge from McClenaghan.
The youngster, an emerging talent in the sport, signalled his intention with a composed routine which was rewarded with 15.100 - the same total he had managed in qualifying.
Whitlock often saves his best until last and is known for keeping some of his tougher tricks up his sleeve when competing in finals but it was not enough this time as his execution score was 0.300 less than McClenaghan.
A visibly emotional McClenaghan collected a Northern Irish flag from the crowd after his triumph was confirmed as he celebrated a victory he could scarcely have thought possible.
Whitlock was forced to settle for silver and Zachary Clay of Canada took bronze on 14.300.
"Of course when the scores came up, it stunned me a little bit," McClenaghan said.
"But then I remembered that the highest execution score takes the top spot.
"I was proud that I beat the world champion.
"I just can't describe the feeling of coming at the top today."
Olsen then emerged triumphant from her duel with compatriot Ellie Black, crowned women's all-around champion yesterday, as she won the vault with an average of 14.566 points.
Black, a World Championships silver medallist last year, was second on 14.233 and bronze was claimed by Australia's Emily Whitehead.
Tulloch was expected to be among the contenders in the rings final and he lived up to his billing with a dominant display.
The 22-year-old double European Championships medallist was the first to compete and set a benchmark which proved insurmountable by scoring 14.833.
Tulloch led a one-two for England as Nile Wilson, winner of the men's all-around yesterday, took silver on 14.400.
Canadian Morgan may have been dethroned but he returned to the podium, claiming bronze with a score of 14.000.
Fenton rounded off the first day of apparatus finals as she secured her maiden individual major medal with gold in the uneven bars on 14.600.
Canadian Brittany Rogers did enough for silver as she scored 14.200 and Australian Georgia Godwin, the last to compete in the event, earned bronze with 13.433 points.
The artistic gymnastics programme at Gold Coast 2018 concludes tomorrow.