The star scrum-half was in fine form with the boot, sending over the winning score with seven minutes remaining in South West London.
Yachvili outshone England's World Cup winning hero Jonny Wilkinson from the tee, a man whose name is synonymous with winning big games with the boot.
But rather than focus on his own stellar performance in securing Heineken Cup qualification for his side at the last possible attempt, Yachvili chose to dedicate the win to every single member of a Biarritz squad that finished the season in superb style after an otherwise disappointing year.
"I think there are two words to sum up our victory: solidarity and team spirit," said Yachvili, who previously played in two losing Heineken Cup Finals with Biarritz back in 2006 and 2010.
"We never gave up until the last second, until the last ruck, the last tackle.
"It's a victory for the full squad and not just the 22 or 23 players who played on the night. It's also a victory for all our supporters and all our staff."
As for the kicking itself, Yachvili pointed towards hard work as the reason behind his heroics.
While Wilkinson has earned plenty of plaudits for the hours he devotes to his own practice, Yachvili's work on the training pitch has always been less publicised but no less important.
"I did my job as a goal kicker and I'm very proud and happy because there's a lot of work behind it," added Yachvili.
"I'm very happy about my goal kicking success and delighted to score after the efforts of my team-mates.
"There's no comparison to make with Jonny Wilkinson, though, because for me he is a true gentleman, a terrific player."