|2016 Track Cycling World Championships|
|Venue: Lee Valley VeloPark, London Dates: 2-6 March|
|Coverage: Live BBC coverage on TV, radio and online. Click for listings.|
Jess Varnish and Katy Marchant criticised Great Britain's selection policy after failing to secure a team sprint place at the Rio Olympics.
The pair missed out after finishing fifth at the Track Cycling World Championships in London.
That failed to secure them one of five Olympic qualifying sports for European nations.
"I feel sick," said Varnish, who was disqualified at London 2012 when competing with Victoria Pendleton.
"How many more times can I keep putting my life on hold, making these choices for my career, if it's not going to pay off, through no fault of our own?"
'Bad decisions and bad luck'
Varnish and Marchant needed to finish three places in front of France to take the fifth slot available to European teams but the French were seventh.
British Cycling head coach Iain Dyer stood by the decisions made over the two-year qualification period.
"I fully understand their disappointment, but we've done the best we can on every possible turn," he said.
"When we look back on our two-year qualifying period, I honestly don't think that we can consider there would be much we would change."
However, Varnish, who could yet go to Rio in the individual sprint and Keirin, laid the blame firmly with her coaching team.
"We have been basically playing catch-up through bad decisions and bad luck," said the 25-year-old from Worcestershire.
She said that inexperienced riders had been given chances to compete at major championships when the focus should have been on ensuring more senior members qualified for the Rio Games, which take place in August.
"To have to qualify for the Olympic Games, it should not be a development programme," said Varnish. "It should be 'A team', 'A team', 'A team'.
"We're fifth in the world, we've beaten so many of the teams, this is the best we've ever competed and we're not going to the Olympics."
Marchant, 22, said it was "heartbreaking" to miss out, adding: "We should never have been in the position that we're in today."
The men's team of Philip Hindes, Jason Kenny and Callum Skinner have already qualified for Rio but also struggled in London, finishing sixth.
Three-time Olympic champion Kenny said: "It was a massive step forward. The main thing is that we're in the ballpark. We're right there."
New Zealand took gold in the men's sprint and Russia won the women's title.
Victoria Pendleton, double Olympic champion
"I love Jess dearly and her experience in London was tough. I feel very sad that they won't get a chance to ride the team sprint at the Olympics because I really do think they have got the right ingredients there and they could find a very successful team.
"It breaks my heart. It won't be easy for the girls to go to sleep tonight, but there's always another day and there's always another chance to ride.
"The best thing about it is those girls are still so young. I didn't start track racing until I was in my early twenties. Tese girls have already got three of four years' training on me and they've got plenty more Olympic chances ahead of them.
"I just hope they use it and push themselves. They'll get there."
Wiggins impresses on track return
There was better news for Britain's team pursuit men as they qualified fastest earlier on day one.
Sir Bradley Wiggins made a strong start to his first Track Cycling World Championships for eight years alongside Steven Burke, Jonathan Dibben and Owain Doull, clocking three minutes 55.664 seconds in the team pursuit.
Britain will take on Italy (3:57.800) in Thursday's semi-finals.
Australia (3:55.867) and defending champions New Zealand (3:57.050) will meet in the second semi-final.
Wiggins, 35, is targeting a fifth Olympic gold medal in Rio and a British record eighth medal in all.
Chris Latham, 22, finished ninth in the scratch race on his World Championships debut, with Spain's Mora Vedri taking gold.
Australia's Rebecca Wiasak beat Poland's Malgorzata Wojtyra to retain her individual pursuit title.
Former Olympic champion Chris Boardman
"The British team did what we expected them to. They're there or thereabouts. There were disappointments and real promise.
"The men's pursuit team were really ragged but did an incredible ride to still qualify fastest. The Australians looked as if they still had plenty left to give, so it's going to be an incredible final. It looks like they could be back on track for gold in Rio and here.
"The women's team sprint was obviously disappointing, but the British team has always said they're about gold medals and if you're trying to get to the Olympic Games it's nice for the individual, but the programme is funded for Olympic golds.
"If you haven't got a team that you genuinely believe can win a gold medal, then it's reasonable to try different combinations, even if it means not qualifying. I would have gone with the strategy the coaches deployed."