Fabian Cancellara reclaimed the race leader's yellow jersey as the Tour de France endured another bumpy ride today.
The 213-kilometres from Wanze in Belgium to Arenberg Porte du Hainaut was one of the most dramatic in recent memory as the cobble stones shook up the general classification standings.
Thor Hushovd (Cervelo Test Team) emerged victorious as the 97th Tour entered France for the first time, but Cancellara (Team Saxo Bank) returned to the top of the standings after leading team-mate Andy Schleck back into contention.
Andy Schleck hit the tarmac twice in a crash-strewn stage in the Ardennes region of Belgium yesterday, one which saw Sylvain Chavanel (QuickStep) take the yellow jersey.
But Cancellara returned to the maillot jaune today, enhancing Andy Schleck's hopes of overall victory in Paris on July 25.
He will have to do so without the support of his brother Frank Schleck, who abandoned after crashing on the fourth of seven cobbled sections.
Geraint Thomas (Team Sky) was second to Hushovd in the sprint finish and now lies second overall, 23 seconds behind Cancellara.
Cadel Evans (BMC Racing) is 16 seconds further back after finishing in the lead group today, while Alberto Contador (Astana) fell two places to ninth and Lance Armstrong (Team RadioShack) dropped back from fifth to 18th after becoming the victim of a puncture.
Team Sky leader Bradley Wiggins finished in the second group, moving up to 14th overall, one minute 49 seconds behind Cancellara.
Hushovd took control of the points classification rankings by sprinting to victory and earning the green jersey for tomorrow's stage.
He said: "To win on this day on the cobble stones really means a lot to me.
"The team was perfect today. I really want to compliment them. They were really motivated and they gave me so much help to keep me in a good position.
"I needed to stay in the front group and avoid trouble, I knew I would have a good chance. That's what I did and I was able to win."
Seven cobbled sections - some of which feature in the Paris-Roubaix spring classic - totalling 13.2km tested the peloton to the full.
Three pave sections were in Belgium and four came in the closing 30km in France - the first of which accounted for Frank Schleck.
He was seen lying in the middle of the road in a foetal position and was the latest casualty of a tumultuous first four days of the Tour.
Ryder Hesjedal (Team Garmin-Transitions) was the catalyst for an early seven-man escape and later forged forward on his own, only to be caught by a five-man group of Hushovd, Cancellara, Andy Schleck, Evans and Thomas.
Hushovd, defending the sprinters' maillot vert he won in 2009, was then always likely to win the sprint for the line.
It was a day billed as one which could break the hopes of the general classification contenders, with Armstrong predicting "carnage".
He was a victim of the brutal ride, suffering a flat tyre in the closing stages which cost him crucial time.
Tomorrow's anticipated sprint finish on the 153.5km stage from Cambrai to Reims will give the general classification contenders a chance to recover, with the Alps swiftly approaching.