Farrar has ridden with a broken wrist since a crash on stage two, and even managed third in the bunch sprint on Thursday, but he packed mid-stage after being dropped early in the company of Lars Boom (Rabobank).
When he was then left behind by Boom he climbed off. "Even if he'd kept going he'd have missed the time limit," said his team director, Matt White.
Farrar said: "I am devastated to leave the Tour and my teammates. You never want to leave any race, but especially the Tour. It's the event we work for all year. I've been suffering since my crash on stage two and today the pain was just too much."
White explained that, while Farrar could overcome the pain to sprint, he paid for the effort the following day. "Sprints are easier for Tyler to get through because the adrenaline in that situation helps mask the pain.
"Today was the hardest day of the race so far and the kind of climbing and descending these guys did is incredibly painful for an injury like Tyler's. Having to brake on the descents is probably the most painful thing to do with a broken wrist.
"We're obviously sad to see him go but, at the end of the day, his health comes first. Tyler won't be able to heal until he goes home and rests and that's what he'll do from here."
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White said that Farrar would ride the Vuelta a España, with his focus on the world championships in late September. "The world champs course is super for him," he said, "so that's definitely a goal."
Jonathan Vaughters, the team's CEO, noted that the team has lost three riders, and suffered at least as many broken bones. "We may not have luck on our side at the moment but we have a team of great, tough riders who will continue to be competitive here," said Vaughters.
As to the team's revised priorities, having lost its sprinter Farrar and leader Christian Vande Velde, White said they'd target stages. "We'll for stage wins, for sure," he said. He even managed a joke as he contemplated what the squad might do if they lose any more: "If it gets to one or two we'll send the bus home."
Richard Moore is a freelance journalist and author. His first book, In Search of Robert Millar (HarperSport), won Best Biography at the 2008 British Sports Book Awards. His second book, Heroes, Villains & Velodromes (HarperSport), was long-listed for the 2008 William Hill Sports Book of the Year.
He writes on sport, specialising in cycling, and is a regular contributor to Cyclingnews, the Guardian, skyports.com, the Scotsman and Procycling magazine.
He is also a former racing cyclist who represented Scotland at the 1998 Commonwealth Games and Great Britain at the 1998 Tour de Langkawi
His next book, Slaying the Badger: LeMond, Hinault and the Greatest Ever Tour de France, will be published by Yellow Jersey in May 2011.
Another book, Sky’s the Limit: British Cycling’s Quest to Conquer the Tour de France, will also be published by HarperSport in June 2011.
