Olympic Champion Kat Copeland and Charlotte Taylor, the reigning European Champions, set a world best of time of 6:48.38 to win their world cup semi-final in Varese, Italy, today, and become one of 11 GB boats into tomorrow's finals.
Neither was aware of their record breaking achievement as they focussed on "keeping the rhythm under pressure" in a race from which the second GB light women's double of Imogen Walsh and Ellie Piggott also made the final.
Helen Glover and Heather Stanning, the reigning World, Olympic and European Champions, came through a tough test against fast crews from the USA, Australia and New Zealand to win their women's pair semi in style.
"Races like that are all about the culmination and fruition of all the hard work", said Glover. Stanning added: "The depth of field in the women's pair is growing as it's Olympic qualification year and that can only be good for the event".
The GB Rowing Team women's eight also maintained the form that saw them run America's World and Olympic Champions close in yesterday's heat. They led throughout their repechage and won with something to spare in 5:59.90.
Richard Chambers and Will Fletcher were not pleased with their performance behind the French in today's light men's double semi but are safely through as are the recently-formed men's pair of Mat Tarrant and Calum McBrierty, Alan Campbell in the men's single and the men's open and lightweight fours.
John Collins and Jonny Walton will probably not find consolation in the fact that their semi was the most exciting of the day. Only half a boat length separated the four top crews in this race for all bar the final 10 stroke surge in which the GB boat found themselves nudged into fourth and out of tomorrow's final.
Today's qualifying boats join the men's eight - featuring Olympic Champions Peter Reed and Alex Gregory as well as a host of World winners from 2013 and 2014 - and the men's quad who are already into finals having won their heats yesterday.
Sir David Tanner, GB Rowing's Performance Director, said: "We've done well today to achieve 11 A final places from 13 with two boats in the lightweight women's double A final. This puts us in a great position tomorrow to challenge in those finals in what must be the best world cup field that we have seen in this Olympiad so far".
By halfway the GB duo had a decent lead but New Zealand put in a push just after halfway to get ahead of America and Australia.. Glover and Stanning edged further ahead in this phase and as the crews came in sight of the grandstands they looked in control, going on to win in 6:53.04.
The USA came through with 350m to go and got past New Zealand who took third with Australia in fourth. America won the opposing semi-final with Denmark and France also qualifying.. In this race the GB's development combination of Rebecca Chin and Karen Bennett, both making their debuts here, were sixth in 7:19.48.
Calum McBrierty and Mat Tarrant, the second-ranked GB men's pair, reached today's semi-final through the repechage yesterday. In the first half they remained in contention in fourth place in a race led by the Netherlands. With 500m to go, the British boat took up the chase with a zippy and long sprint which saw them surge past the Czech Republic to gain the third and final qualifying place along with race winners the Netherlands and Australia.
Richard Chambers and Will Fletcher are already European silver medallists and knew that today's semi-final would be another chance to measure themselves against the world's stand-out crew, Stany Delayre and Jeremie Azou of France, who won the European title in Poznan three weeks ago.
The French took an early lead with the British tucked in behind and the USA in third. With the race half-way over, the French had what looked like an unassailable lead and the British could not make an impact but they had a clearwater advantage over Andrew Campbell Jr and Joshua Konieczny of the USA.
In the final sprint to the line, the French held their lead and were able to relax whilst the GB boat held off a final sprint from the Americans. Italy won the other semi-final.
"That didn't go to plan, to be honest", said Chambers. "The French got the jump on us and left us too much to do in the second half. That wasn't our best row".
"Richard's right. That wasn't what we wanted today. It's good that tomorrow we have the chance to put in something better", said Fletcher.
Kat Copeland and Charlotte Taylor made a big impression in winning the European final in May. They were in strong form in the heat to qualify for today's lightweight women's double semi-final. Germany and the GB boat were locked tightly with the British boat just hundredths ahead of Fini Sturm and Marie-Louise Draeger.
In the same race Imogen Walsh and Eleanor Piggott were also representing Great Britain and eased up into third as the race went through the halfway point. Out front the top British boat moved away from Germany to secure the win in 6:48.38 - a new world best time.
Behind them, the second British boat dug in and began to make ground on the Germans. Roared on by the travelling British spectators Walsh and Piggott got within half a length at the finish to take the third qualifying slot in 6:52.63. New Zealand, the World Champions, won the opposing semi-final in 6:50.68.
"We weren't really aware of the world best time. We just wanted to focus on what we were doing", said Taylor afterwards.
"Today the aim was to keep the good rhythm of yesterday if we were under pressure and we did. I'm pleased with that", added Copeland.
Alan Sinclair, Nathaniel Reilly O'Donnell, Tom Ransley and Scott Durant held third spot in the opening 500m of their men's four repechage today. Canada were leading with Argentina and then Italy moving up not second.
The British quartet moved into second just before halfway and held onto that as Italy faded to a length behind GB whilst Cuba mounted a challenge. Aware of the danger Durant picked up the pace and the British went through in second place in a time of 5:51.64.
Great Britain's women's quadruple scull of Melanie Wilson, Tina Stiller, Beth Rodford and Jess Leyden were so close to qualifying from their repechage today that it hurt to watch. In the final phases they were battling back and eating into the lead held over them by New Zealand in second in a race won by Australia. Only two went through to the final.
The lightweight men's four finished their semi in second to Switzerland. The two lead boats were close for much of the first half before the Swiss gained the advantage somewhat. China, in third, were a threat for some time before dropping back.
Jonny Walton and John Collins, in the GB men's double scull, must have known they were in a prize-fight today. As the crews moved up to the halfway of their race there was less than half a boat's length between the top four crews - including the Leander Club combination.
"What a semi!", roared the local race commentator as the pitch of his delivery rose and rose.
With 500m to go the British crew had the slenderest of leads and the danger was that any of the four boats could take the top three qualifying spots. Important now to hold on to the rhythm. under pressure and keep the boat speed.
Collins and Walton dug deep but so did the other three crews as the crowd were on their feet. In the end the British were an agonising fourth in 6:10.43 with the winner, Argentina, taking the honours in 6:09.77. Italy took second and the Australians taking third by just two tenths of a second.
Katherine Grainger, the Olympic Champion, and Vicky Thornley were in the lead at the halfway mark - but by a sliver - in their women's double scull semi-final. Only one hundredth of a second separated them from Germany in second. About the width of a duck's feather.
The USA were third and Belarus were still a danger. By the time the crews came into view against the backdrop of the mountains, the GB boat had 0.4 of a second over Germany with USA coming up quickly on the leaders.
Indeed it was the USA who found the legs to push past the leaders in the final sprint to the line, pulling Germany though with them as Thornley and Grainger took third in a relatively close finish.
Cox Zoe de Toledo must have been pleased with the GB women's eight's first-half repechage delivery today. They had the early lead but from a tightly bunched field once more. With the race moving to the halfway point the Chinese mounted a challenge with Australia and Germany in third and fourth.
Four places were open to crews wishing to reach the final. The GB boat continued to keep the lead in the third quarter of the race with perhaps a length over the field. In the final 500m " the British crew looked rock solid. The final awaits for Katie Greves, Olivia Carnegie-Brown, Jessica Eddie, Donna Etiebet, Vicky Meyer-Laker, Louisa Reeve, Rosamund Bradbury, Zoe Lee and Zoe de Toledo.
Alan Campbell led out his open men's single scull semi-final an was the race leader after 500m. In a somewhat interesting middle two quarters he was sixth and then burst through to take up third place which he held to the line. Mahe Drysdale of New Zealand had earlier eked his way up the field before surging into a lead which he held to the line in 6:41.93. Cuba's Angel Fournier Rodriguez was second.