Edvald Boasson Hagen secured Team Sky's first Tour de France stage victory, in wet conditions on Wednesday.
Boasson Hagen was led out by team-mate Geraint Thomas in stage six as he stormed to his maiden Tour stage win.
"I am really happy," said Boasson Hagen. "I did a good sprint and Geraint did a really good lead out as well."
HTC-Highroad rider Matt Goss was second in the sprint finish, while Thor Hushovd retained the yellow jersey after finishing third.
The riders had to endure torrential rain at times on a punishing 226.5km stage from Dinan to Lisieux, the longest stage of this year's event.
The stage began with an attack by five riders. Anthony Roux (FDJ), Leonardo Duque (Cofidis), Adriano Malori (Lampre-ISD), Johnny Hoogerland and Lieuwe Westra (both Vacansoleil) broke clear at the five-minute mark and at one point, the quintet established a lead of over 11 minutes.
Malori and Westra remained out in front as the peloton caught the other three riders and with 38km to go, the duo held a lead of over two minutes.
Westra ended his charge with 18km left, and Malori was caught 2.6km from home with the steep climb to come.
The rain had made the roads treacherous but the HTC-Highroad team pushed their way to the head of the peloton, while last year's winner Alberto Contador, who changed bikes twice with 30km left, also moved near the front along with Jelle Vanendert.
Thomas Voeckler took the lead with 2km to go but he could not hold on and, in the chase to the line, the in-form Thomas led out Boasson Hagen, who took the lead with 200m to go and crossed first for the biggest win of his career.
"I really surprised myself," said Boasson Hagen. "Lots of people say that I'm a talented guy, so it's nice to show it by winning a stage.
"I was feeling strong and I knew from yesterday that I had the legs so the chance was there - I'm so glad we were able to take it.
"It's hard to describe the emotions, I'm just so happy. To get my first stage at the Tour de France is so special."
Thomas, who played a key role in the victory, paid tribute to all the members of Team Sky after the win.
"It's been a great start to the race for the team and we knew we could do something today," he said.
"I tried to deliver him as best I could and he finished it off perfectly. The whole team played their part, it was just a great all-round team effort."
Team Sky competed in their first Tour de France in 2010 and they have the aim of winning the event within five years.
And team principal Dave Brailsford said he was elated with Hagen's victory.
"The bus nearly turned over we were jumping up and down so much," said Brailsford. "It's a huge moment for the team - we're not even a year and a half old and we've won a stage of the Tour de France.
"We're ambitious people - we always have been - and we sometimes get criticised for that.
"We had a tough Tour last year - everyone knows that. But if you don't aim high in life you're not going to get anything."
Boasson Hagen's win completed a memorable day for Team Sky, for whom Ian Stannard won his first professional victory, on stage five of the Tour of Austria.
Stage 6 result:
1. Edvald Boasson Hagen (Nor/Team Sky) 5 hours, 13 minutes, 37 seconds
2. Matthew Harley Goss (Aus/HTC-Highroad) same time
3. Thor Hushovd (Nor/Garmin-Cervelo)
4. Romain Feillu (Fra/Vacansoleil-DCM)
5. Jose Joaquin Rojas (Sp/Movistar)
6. Arthur Vichot (Fra/Francaise des Jeux)
7. Philippe Gilbert (Bel/Omega Pharma-Lotto)
8. Gerald Ciolek (Ger/Quick Step)
9. Marco Marcato (It/Vacansoleil-DCM)
10. Arnold Jeannesson (Fra/Francaise des Jeux)
1. Thor Hushovd (Nor/Garmin) 22 hours, 50 minutes, 34 seconds
2. Cadel Evans (Aus/BMC) +1"
3. Frank Schleck (Lux/Leopard-Trek) +4"
4. David Millar (GB/Garmin-Cervelo) +8"
5. Andreas Kloeden (Ger/RadioShack) +10"
6. Bradley Wiggins (GB/Team Sky) same time
7. Geraint Thomas (GB/Team Sky) +12"
8. Edvald Boasson Hagen (Nor/Team Sky) same time
9. Jakob Fuglsang (Den/Leopard-Trek)
10. Andy Schleck (Lux/Leopard-Trek)