The flagship men's four won a thrilling gold as Great Britain claimed four medals on the final day of the World Rowing Cup in Lucerne.
Alex Gregory, George Nash, Mo Sbihi and sub Callum McBrierty overhauled Australia in the final two strokes to win by 0.27 seconds.
There was also silver for the men's quad and bronze in the men's pair.
Perhaps the most surprising result came in the women's eight, with the crew adding a silver to their European gold.
That came amid speculation that two of their number could be dropped for the Rio Olympics to accommodate Katherine Grainger and Vicky Thornley.
"There's a selection question but this crew is capable of winning gold at Rio," cox Zoe de Toledo told BBC Sport.
"If it's made stronger, great, but if this is the crew we have I'm really excited about the next few months."
Britain were denied a predicted gold medal in the opening final of the day when Olympic champions Heather Stanning and Helen Glover pulled out of the pair.
Stanning was one of several members of the squad who fell ill overnight, with Peter Lambert also stricken by a bug.
However, the quad still delivered a silver in his absence, with Jack Beaumont joining Sam Townsend, Angus Groom and Graeme Thomas to hold off a late challenge from Switzerland and claim second behind Australia.
"That was proper last-minute stuff - an hour-and-a-half before - and we did our first stroke in the warm-up and nearly capsized," Townsend told BBC Sport.
The European Championship-winning four were also rowing with a substitute after Constantine Louloudis pulled out earlier in the week and struggled before one of the Australians caught an oar in the water in the second last stroke.
"I actually thought we'd lost it on the line because the Australians were shouting," said replacement McBrierty.
Nathaniel Reilly-O'Donnell and Matthew Tarrant completed Britain's medal haul with bronze in the pair, having finished behind New Zealand in the same time as the Dutch runners-up.
Britain sealed their first gold of the regatta on Saturday through the non-Olympic lightweight men's pair of Sam Scrimgeour and Joel Cassells.