SAINT-QUENTIN, France -- The Tour de France is shadowed again by Lance Armstrong and doping.
The subject returned with a vengeance to cycling's greatest race Thursday, and caught in the turmoil were four riders and a team manager who years ago helped Armstrong on the way to his seven Tour titles.
All this on a day when Germany's Andre Greipel won the fifth stage -- his second in a row -- in a sprint after the 122-mile trek from Rouen to Saint-Quentin, north of Paris. Fabian Cancellara kept the race lead for a sixth straight day.
The ride got off to a bumpy start after a Dutch newspaper reported the former Armstrong teammates cut a deal with the U.S. Anti-Doping Agency for their testimony in a doping case against him.
Daily De Telegraaf, citing "well-informed sources," said USADA had given six-month bans to Jonathan Vaughters, George Hincapie, Levi Leipheimer, David Zabriskie and Christian Vande Velde.
Later Thursday, The New York Times reported online that four of those riders -- all but Vaughters -- would testify in the agency's case. The paper cited two unidentified people with knowledge of the case who requested anonymity because the investigation was ongoing.
Vaughters, now a team director at the Garmin-Sharp team, called the Dutch report "completely untrue." The others declined to comment, though Hincapie said his thoughts were with Armstrong.
"I'm sad he is going through this," said Hincapie, the only rider to have been on all of Armstrong's Tour-winning teams. "He's done so many things for the sport. His accomplishments are incredible."
The revelations amount to a new twist in a swirling drama over the legacy of cycling's greatest global superstar -- this time putting some of his former friends and teammates on the spot.
USADA refused to confirm the report, while cautioning in a statement that the five named could be subject to "unnecessary scrutiny, threats and intimidation."
As is often the case, the riders are likely to put their heads down, and hope that the affair blows over in time. Vande Velde and Zabriskie rode away from questions about the issue before Thursday's start.
But it's a cloud that could chase them throughout the Tour, an additional complication and distraction in a sport that's already physically and mentally grueling. Vande Velde, who crashed this week, and fellow Garmin-Sharp rider Zabriskie want to help Canadian teammate Ryder Hesjedal win the Tour. Leipheimer, the leader of the Omega Pharma QuickStep team, has long-shot victory hopes of his own.
From afar, Armstrong -- who has unfailingly denied doping during his career -- reiterated his charge that USADA was looking for a "vendetta" against him.
After leaving the Tour for good in 2010, the Texan's travails in the doping case have revived memories of a dark era in cycling in the late 1990s and 2000s when scandals badly tarnished the sport's image. Sport authorities have since taken steps to root out drugs cheats.
Cancellara worried that Armstrong's case might linger over the sport.
"For cycling this is not good, that's for sure," he said. "That makes me sad. But on the other hand, we have to deal with that and I hope it's not something that is going to take three or four years like ... in other cases.
"That is my biggest concern: That this is going to shut down fast."
Garmin, a team that has been vocal in its efforts to crack down on doping, finds itself in the center of the controversy, with three of the five people cited.
The team got another dose of bad news when American sprinter Tyler Farrar had a fourth crash already this Tour, tumbling to the ground as the frenzied pack accelerated with just over two miles to go.
Farrar straggled across the line later alone, blood streaming down his right elbow and knee. He then stormed into the bus of the Argos-Shimano team, looking for its sprinter, Tom Veelers.
Farrar angrily shouted, "You don't do that to someone!"
As in Greipel's sprint-finish victory a day before, the crash tarnished the stage, and he counted himself "lucky" to avoid a spill two days in a row. But this time, the German led a sprinters' dash that overtook three breakaway riders within seconds of the finish.
The top standings didn't change: Bradley Wiggins, the leader of Team Sky, was second overall, seven seconds behind Cancellara. Cadel Evans of Australia, the defending champion, was 17 seconds back, in seventh.
By holding his lead, Cancellara earned the right to wear the coveted yellow jersey for the 27th time in his career, a record for a rider who has never won the Tour.
"When you make history in this kind of way at the Tour, it's more special," said Cancellara, a time-trial specialist and the only man to don the yellow this year after winning Saturday's prologue.
The Swiss rider has said he doesn't expect to hold on to the yellow jersey after the race enters the Alps in Week Two -- where climbers will take the limelight. The three-week race ends July 22 in Paris.
The race got its first minor dose of rain Thursday, and another dropout: Germany's Marcel Kittel, who has endured gastric troubles for the last few days, pulled out to reduce the field to 194 riders.
Friday's sixth stage -- a 128-mile jaunt from Epernay in Champagne country to Metz -- offers the last leg in the northern flats this week to favor sprinters, before a steep uphill finish Saturday.
AP Sports Writer Samuel Petrequin and Associated Press writer Greg Keller contributed to this report.