David Millar out-sprinted his breakaway companions to claim victory on Tour de France stage 12.
Twelve years after winning the prologue on his Tour debut, the 35-year-old Scot was triumphant on the 226-kilometre route from Saint-Jean de Maurienne to Annonay-Davezieux after a day-long escape.
Millar (Garmin-Sharp) won the dash to the line from Jean-Christophe Peraud (Ag2r La Mondiale), who finished second after the duo broke clear of their other breakaway companions in the final 3km.
It was the fourth British stage win of the 2012 Tour after victories for Team Sky trio Mark Cavendish, Chris Froome and Bradley Wiggins.
Egoi Martinez (Euskaltel-Euskadi) won the sprint for third place, five seconds behind Millar, with Cyril Gautier (Europcar) fourth and Robert Kiserlovski (Astana) fifth.
The peloton contested the race for sixth, with Matt Goss (Orica-GreenEdge) beating Peter Sagan (Liquigas-Cannondale), who was frustrated by the Australian apparently veering off his line in the finale. It was possible Goss would be relegated for the manoeuvre.
Wiggins was part of the peloton which rolled in seven minutes 54 seconds behind Millar and retained the race leader's yellow jersey for a fifth day.
Froome remained second, 2mins 5secs behind, with Vincenzo Nibali (Liquigas-Cannondale) 2:23 back in third and defending champion Cadel Evans (BMC Racing) 3:19 adrift in fourth.
But the day - the 45th anniversary of the death of Britain's first maillot jaune, Tom Simpson - belonged to Millar, the most recent Briton to lead the Tour before Wiggins.
It was an emotional success after a two-year suspension following his admission in 2004 that he took the banned blood-booster EPO.
Millar, now a fervent anti-doping campaigner, won the 13th stage to Bezier in 2002, but asked for his time-trial win on stage 19 in 2003 to be wiped from the record books after his confession.
His attempt to win in Barcelona on a solo escape in 2009 was snuffed out by the peloton, but now he has his third triumph in his 11th Tour.
Two weeks tomorrow Millar is set to compete in his first Olympics in 12 years after the British Olympic Association's bylaw banning those with prior doping bans was scrapped.
Millar was in the early break on the longest day of the 99th Tour.
The route was always likely to favour an escape, with two category one climbs early on and a category three ascent in the final 20km as the peloton headed south and the general classification contenders recovered from their Alpine excursion.
The Scot was one of 11 riders in the lead after 60km, with the best-placed overall Kiserlovski (Astana), who began the day 28:43 behind Wiggins.
Millar was fourth over the day's second first category climb, the Col du Granier, and attacked on the descent as a group of five leaders formed.
He was joined by Kiserlovski, Martinez, Peraud and Gautier and the quintet established a substantial lead.
The five leaders were more than 11 minutes ahead with 86km of the stage remaining as world champion Cavendish, among the riders dropped earlier when ascending the major peaks, returned to the peloton.
Cavendish opted not to contest the intermediate sprint and fell further behind green jersey incumbent Sagan (Liquigas-Cannondale).
The world champion, who was performing bottle-fetching duties for Team Sky, then punctured and was reprimanded by race commissaries for passing by team support vehicles on the wrong side when returning to the peloton.
Millar was the only previous stage winner in the break, which had a 12:10 advantage over the peloton with 25km to go.
The quintet crested the summit of the short, sharp category three climb of the Cote d'Ardoix together, but with a long uphill drag to the finish, further drama was expected.
With 3km to go Millar led, but he and his companions played a watchful role before Peraud accelerated forward.
Millar followed him, but the other three could not.
Millar and Peraud had a lead of more than 50 metres which was increasing as they went under the 2km to go mark.
The chasing trio appeared reluctant to work together and Peraud and Millar were also lacking cooperation when the Scot took to the front.
Peraud made his bid for victory with 200m to go, but Millar summoned the strength to hold off his younger companion and punched the air with delight before collapsing in exhaustion over the line.
It proved he was back to full form after fracturing his collarbone in March.
Now all four of Britain's Olympic road race team riding the Tour have won a stage. Ian Stannard will complete the five-man line-up on July 28 but was not selected by Team Sky.
Further British success could follow tomorrow, with Cavendish eyeing the 217km 13th stage from Saint-Paul-Trois-Chateaux to Cap d'Agde, on the shores of the Mediterranean.