The Velodrome once more revealed itself to be a fickle and infuriating beast yesterday in a dramatic afternoon that saw Britain clinch gold but taste the bitter disappointment of disqualification in the space of 15 minutes.
With a stunning performance in the C1 pursuit, Mark Colbourne stormed to victory in world-record-breaking time – an astonishing achievement for a man who was laid up in hospital with a broken back three years ago after a paragliding accident.
For the thousands of fans it was a desperately needed triumph after Jody Cundy, one of Britain's most successful paralympic athletes, was disqualified minutes earlier. The defending Paralympics champion, and the fastest man in the field, saw his dreams of gold in the 1km time trial crumble as his back wheel span as soon as it left the starting blocks. Cundy stopped peddling and called for a restart but officials argued it was his error, not a mechanical one, and struck him out of the race.
The shock disqualification left Cundy incandescent with rage as he threw a bottle of water on the floor and gave a two-fingered salute to officials.
Fighting back tears after being told he could not defend his title, he roared at officials: "Do you know what it's like to work so hard for four years for a one- minute-three-second race in front of 6,000 people and then not be allowed to ride the race? I'm never going to have the opportunity again."
His girlfriend, a press photographer, was also crying trackside. Cundy will have another chance to go for gold in the individual pursuit. He later returned to apologise to the crowd and received a rapturous applause.
Louis Barbeau, the International Cycling Union technical delegate, defended the decision: "To have a restart you have to have had a recognised mishap: either a puncture, a fall or breakage. Our interpretation is that the rider put too much weight on the front wheel, and as a result the back slipped."
Elsewhere it was another dramatic day of highs and lows for Paralympics GB. Hannah Cockcroft won Britain's first track gold when she triumphed in the women's 100m T34 sprint in a Paralympic record time. Earlier, Welshman Aled Davies collected Britain's first athletics medal at the stadium yesterday with a stirring performance in the F42/44 shot put that earned him a bronze.
The swimming brothers Oliver and Sam Hynd won silver and bronze respectively at the aquatics centre in the S8 400m freestyle. In the women's equivalent, Heather Frederiksen won silver in a race which saw USA's Jessica Long knock more than two seconds off the world record.
But the there was heartbreak too. Stephen Miller, the athletics team captain, who has cerebral palsy, failed to qualify for the final round of the F31/32/51 club throw competition. He had been a favourite having taken gold at Atlanta, Sydney and Athens and silver at Beijing. His failure mirrored that of the Olympics athletic captain, Dai Greene, who was also knocked out in the early stages. "Usually I do well in big competitions," said Miller. "It just didn't happen. I can't put my finger on it."
Cundy was not the only athlete to feel aggrieved. A data recording error in the women's F35/36 discus meant that wrong podium positions were given out during the medal ceremony. The organisers had to apologise after the Ukrainian thrower Mariia Pomazan stepped up to receive her gold only to find out that she had been downgraded to silver. Her Chinese rival Qing Wu went from silver to gold while the Australian thrower Katherine Proudfoot climbed from fifth to third, knocking China's Bao Jiongyu off the podium altogether.
But the day also provided moments of inspiration. At the ExCel centre yesterday morning Martine Wright, who lost both her legs in the 2005 terrorist attacks in London, came out to represent her country in the women's sitting volleyball team against Ukraine.