ParalympicsGB cyclists win a gold in the 3,000m pursuit, but suffer a controversial decision in the 1km time trial.
Mark Colbourne cycled to victory in the C1 pursuit, breaking the world record that he had set earlier in the day at the same time. Colbourne raced the track in 3:53.881 against silver medallist Li Zhang Yu.
However, the velodrome had seen controversy in the previous cycling event, the C4-C5 1km time trial, in which gold medal hopeful Jody Cundy was given a "did not finish" result after what appeared to be a fault with the starting gate.
Speaking after the decision Cundy said: "I fell out of the gate because the f****** gate didn't open. I've wasted four years of my life to ride in front of 6,000 people.
"Do you know what it's like to dedicate four years of your life? I can't even express it. There aren't the f****** words. I'll never, ever get this opportunity again. Never, ever. What am I supposed to do now?"
Cundy, who was the last to race, was disqualified after a failed attempt to start the race. It appeared that Cundy was held by the gate, which holds the back wheel before the cyclists set off.
Cundy tried to get a restart in the race, saying the gate was faulty. However, the Spanish team protested and officials ruled Cundy should have carried on cycling.
Despite protests from the British team, officials decided that Cundy "did not finish", putting him in last place. ParaGB members rushed to calm Cundy who was understandably upset at the decision.
In footage shot directly after the race (below) you can hear Cundy's fury at the decision when so many other restarts have been given in previous races. There will be no chance of any further appeal to the decision.
Giles Long MBE, Paralympic gold medallist, voiced his fury at the decision - saying Cundy was "robbed".
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Cundy will ride again on Saturday in the men's individual C4 pursuit.
His race followed that of Butterworth who was fractions of a second behind gold medal winning Spaniard Alfonso Cabello, and claimed silver.
In the C3 cycling pursuit ParaGB's Shaun McKeown won silver and Darren Kenny won bronze. The USA's Joseph Berenyi took gold.
Butterworth and Cundy were third-from-last and last cyclists to race respectively. As Butterworth took to the track the gold medal position was held by Cabello, the fourth-last cyclist, who had just broken the world record previously set by Butterworth.
Butterworth, in his Paralympic debut, raced the course in 1:05:985 - a fraction of a second slower than Cabello. The penultimate cyclist was Liu Xinyang, who did not trouble the top spots with a time of 1:07:638.
I am currently swearing very very loudly in my room and using the kind of words that C4 advise against using on twitter. Poor Jody. Gutted.— Giles Long MBE (@gileslong) August 31, 2012
The pair were racing in the C4-C5 classification 1km time trial, in which each cyclist takes to the track individually to race 1km, with the fastest time taking gold. C1 to C5 classifications are for physically impaired cyclists with C1 the most physically impaired cyclists and C5 the least.
Butterworth (C5) is one of Team GB's five military athletes. He lost his left arm in Iraq in 2007 in a rocket attack on Basra air station. Cundy (C4) is a lower leg amputee, born with a foot defect.
Butterworth was a medal hopeful for the race, having picked up the time trial gold in his classification at the Para-Cycling Track World Championship in Los Angeles this year. He was also the world champion the year before.
Because two separate classification compete in the same race for the time trial, a factoring system is applied. This uses the averages of previous races to apply a deduction to the finishing time of the more disabled athletes - a process known as factoring.
Cundy was also a hot favourite having won gold in the 2011 and 2009 World Championships. He was a time-trial gold medallist at the Beijing Paralympic Games.
Like fellow cyclist Sarah Storey, who won ParaGB's first gold yesterday, Cundy started his Paralympic career as a swimmer and won medals, including two golds, at the Atlanta, Sydney and Athens Games.
This morning Aileen McGlynn and her pilot Helen Scott won silver in the B category 1km time-trial for cyclists with visual impairments.
Shaun McKeown and Darren Kenny will also compete for cycling pursuit medals this afternoon after qualifying this morning.