Chris Froome has been given the all-clear to continue in the Tour de France after a bruising first day in France.
After coming through three days in Britain unscathed, the defending champion tumbled to the tarmac early on Tuesday after a touch of wheels in the peloton, but was able to continue before Giant-Shimano's Marcel Kittel took a third stage win out of four.
Froome, who also fell on his left side during June's Criterium du Dauphine, was sent for a precautionary X-ray after his wrist bore the brunt of the fall, but Team Sky announced late on Tuesday that the 29-year-old was okay to continue.
"I took a bit of a knock but I'm happy to make it through the day and get to the finish line without losing any time to my main competitors," Froome said.
"The bumps and scrapes are fine but I fell heavily on my wrist so I needed to get it checked out by the doctors. I'm really pleased that I've been cleared to race and I'm looking forward to getting back on the bike tomorrow."
Froome's joints will face a major test on Wednesday's fifth stage, the 155.5km route from Ypres to Arenberg Porte du Hinaut, which features nine cobbled sections totalling more than 15km.
"The wrist is painful and it's certainly not ideal going into tomorrow's cobbled stage - but I have a great team around me and we'll get through the next few days as best we can," he added.
"One of the riders in front of me overlapped the wheel of another rider and caught my front wheel. I didn't have time to react and I before I knew it I was on the ground. But that's bike racing and I'm pleased I'll be back on the race tomorrow."
Froome may not have lost time, but he dropped back from fifth to seventh in the overall rankings, behind Alberto Contador (Tinkoff-Saxo) and Alejandro Valverde (Movistar).
Froome finished 42nd on the stage, while Vincenzo Nibali (Astana) was 24th to retain the race leader's yellow jersey.
The Team Sky leader's wobble could be significant over the cobbles, where punctures are common, as his team support car will be delayed in reaching him.
The forecast wet weather will make the cobbled stage even trickier for the peloton as the Tour commemorates 100 years since the start of World War One.
Tuesday's stage was expected to be straightforward, but Froome's crash showed nothing can be taken for granted in the Tour.
"Somebody made a mistake," his team-mate Bernhard Eisel said on ITV4.
"This wave went through the whole bunch, from position 10 to the last position in the bunch.
"It's just a big wave and Froomey was like the third rider and with the wave he had no chance. He just went down.
"Even when I stopped and waited for Froomey, he was back on his bike and you saw the last rider crashing near the end of the peloton."
Andy Schleck, the 2010 winner, did not start due to a knee injury suffered in a crash on stage three from Cambridge to London on Monday, when Kittel won.
Another sprint stage was expected in Lille, but that did not put off an early two-man breakaway and Thomas Voeckler (Europcar) continued alone when fellow escapee Luis Mate (Cofidis) was swallowed up by the peloton inside the final 40km.
Voeckler was caught with 17km to go and the sprinters' teams tried to take control, with Omega Pharma-QuickStep to the fore despite the absence of Mark Cavendish, who on Wednesday will undergo shoulder surgery which will put him out for six weeks.
Giant-Shimano lurked menacingly and took over inside the final 2km.
Alexander Kristoff (Katusha) was first to launch his sprint, but despite appearing more laboured than on The Mall 24 hours earlier, Kittel triumphed once more.
Kristoff was second, with Arnaud Demare (FDJ) third.
"It was close today," Kittel, who won four stages in the 2013 Tour and could surpass that 12 months on, said on ITV4.
"We saw that we're not unbeatable. We always need a plan, we always need to concentrate on our sprint and our preparation for our sprint.
"The last 30km we rode with really absolute high speed, always 60 (kph) or more. It was really, really fast, difficult to stay together with the team.
"In the end the boys delivered me in front. I was able to sit there on the wheel of (Omega Pharma-QuickStep's Mark) Renshaw.
"Everything I was thinking about was the last corner. (The team) told me at 250m I could see the finish line and I was almost tempted to go at 500 because I couldn't see where it was, but I sat down again.
"I went really long. I put in everything I had. It was really, really difficult."