Tom Daley and Pete Waterfield finished seventh in the final of the 10m platform synchronised event at the Diving World Cup.
The pair performed well in five of their six routines at London's Aquatics Centre, but one error cost them.
"The 4.5 somersault is one of our newest dives and it's either make of break," Daley told BBC Sport.
"It's helped us before, to win the World Series event [in Sheffield], but today wasn't our day."
The duo, making their debut at the Centre, have suffered an array of injuries since they last competed together at the World Championships in July 2011.
Daley and Waterfield admitted that nerves and a little "rustiness" accounted for their sluggish performance in the morning's preliminary round, where at one point they were down in 10th position.
However, they responded well to the huge applause generated by the home crowd in the evening session, although ultimately they were unable to repeat the bronze medal success of GB team-mates Tonia Couch and Sarah Barrow the previous day.
"The morning was a bit wobbly," reflected Waterfield.
"It was all new, but we got that out of the way and then we could relax and go without that pressure into the final - we just missed our second to last dive which, unfortunately, in these competitions you can do."
Daley added: "The crowd really do help you through the competition and in the first two dives it really did give us that extra buzz and it's going to do that even more in the Olympic games so we're going to look forward to that."
The event was won by Cao Yuan and Zhang Yanquan, China's fifth gold of the World Cup.
In the women's 3m individual springboard competition, Rebecca Gallantree secured Great Britain a place in the event at London 2012 after finishing in ninth position, with a score of 317.85, which qualified her for Friday's semi-finals.
"It was fantastic, the crowd was just amazing, standing on that board and having the whole place cheering for you was just incredible," said Gallantree.
"I was really pleased because I was only one point off my personal best. It would have been nice to get it because my last dive could have been a little better, but overall I have to be happy."
Team-mate Hannah Starling was agonisingly close to joining her, but finished seven points short of Mexican diver Sanchez in 18th position.
Starling will have another chance to attain a second Olympic spot for GB at the Games in Sunday's 'dive-off' where nations can compete for the remaining positions, which have yet to be filled.
In addition to the return of Gallantree, 2004 Olympic silver medallist Waterfield will also be in action in the 10m platform individual event.
"It was good to get a few dives and get a couple of competitions under my belt for my individual," Waterfield told BBC Sport.
"It's the start of the year for us so we have a few more competitions like the World Series so that'll make us competition-fit for the Olympics."