Great Britain's sprint relay woes continued tonight as another baton changeover mistake cost them a place in the 4x100 metres final at the Olympic Stadium.
The host nation were disqualified when anchor leg runner Adam Gemili set off too early as he was about to take the baton from Danny Talbot.
The 18-year-old slowed down dramatically, but the changeover still occurred outside the designated area.
Gemili sprinted for the line and came home second, but the fact he immediately put his hands to his head told the story.
The mistake continues a woeful record for Britain in the event, who, aside from the one glorious exception at the Athens 2004 Olympics, have lurched from one failure to the next.
Dropped batons at the Olympics in Atlanta (1996) and Sydney (2000) and the World Championships in Edmonton (2001), along with a disqualification at the last Olympics in Beijing and the World Championships in Daegu (2011) have ended their chances.
They also went out in the first round at the last European Championships in Barcelona two years ago, while at the most recent Europeans earlier this summer they also failed to get the baton round.
Jamaica, without Usain Bolt, qualified safely, but the United States were the quickest through in a new national record of 37.38 seconds.
Gemili told the BBC: "I went off and maybe I went a bit harder...I don't know.
"We really could have been in contention in the final had we made it.
"It really is disappointing. I think I went on the check mark maybe a tiny bit early."
For Chambers, who ran the second leg, this was almost certainly his last race at an Olympics.
And he was keen to keep his teenage team-mate's spirits up.
He said: "We're proud to have been here representing our country.
"Adam's had a fantastic start to his season.
"This is his first or second season in athletics and he was asked to do a big task.
"I'm proud of him more than anything else.
"We have to build as a team and hopefully can do better throughout the summer and next year."