(CNN) - A sudden gust of wind then a sickening crash.
Chris Froome's ill-judged attempt to take both hands off the handlebars to blow his nose saw the four-time Tour de France champion lose control of his bike and career into a wall at close to 60 kph (37 mph), coming to a shuddering halt.
Froome was out on a training ride at one of the main Tour warmup events, the Criterium du Dauphine, when the freak accident happened last month.
It left the 34-year-old Briton in the intensive care unit of Saint-Etienne hospital with a broken femur, elbow and ribs and with hopes of a record-equaling fifth Tour win in ruins.
According to his Team Ineos boss Dave Brailsford, Froome had been in the form of his life and was a warm favorite for this year's Grand Boucle, which starts in the Belgium capital of Brussels on Saturday.
The British-based team -- previously Team Sky, until securing new sponsorship this year from the multi-national chemical company Ineos, owned by billionaire Jim Ratcliffe -- has provided six of the last seven winners of the Tour de France.
Last year it was Welshman Geraint Thomas who donned yellow for Team Sky at the finish in Paris, with Froome, still tired from Herculean efforts to win the Giro d'Italia only a few weeks previously, in third place.
Froome skipped the Giro this year to specifically target the Tour de France, but his unfortunate absence has thrown the 106th edition of cycling's most famous race wide open, with any number of intriguing possibilities, including an elusive home victory.
Not since 1985, Bernard Hinault's fifth and final triumph, has a Frenchman won their nation's foremost event and it clearly hurts.
A headline in the respected sports paper L'Equipe suggested it was this year or never, hardly a note of optimism for the future of French cycling and placing huge pressures on their main hopes, Romain Bardet and Thibaut Pinot, who have both occupied podium spots in recent Tours, without winning the ultimate prize.
Bardet, who rides for the French AG2R-La Mondiale team, is a renowned climbing specialist, at home in the high mountains of the Alps and Pyrenees, but less assured on the time trial stages on flat or rolling roads, where the likes of Froome and Thomas have previously built up a big time advantages over him.
With only 55 kilometers in total of this type of racing in this year's route, Bardet will indeed probably never have a better chance of making history when the race finishes in Paris on July 28th after 21 stages and with 3,680 kilometers completed.
Groupama FDJ team leader Pinot is better against the clock and has shown encouraging signs of returning to his 2014 form when he finished third in the Tour behind Italy's Vincenzo Nibali, who temporarily broke Team Sky's recent dominance and will be looking to do so again this year, riding for Bahrain-Merida.
Much might depend on how both the Frenchman's teams cope with the tricky team time trial on the second day of the Tour in Belgium, where time lost to stronger outfits such as Team Ineos could prove difficult to make up.
Froome may indeed be missing, but Team Ineos still has a formidable line-up and in 22-year-old Egan Bernal the rising star of the peloton and the hope of cycling crazy Colombia to deliver its first-ever winner of the Tour de France.
Like so many of the Colombian riders, Bernal had the advantage of being being born and developing his talent in the altitude (2,640m) of Bogota, not dissimilar to the advantage enjoyed by Kenyan long distance runners from the Rift Valley.
"This year is a good year for Colombians who are from high altitude, the born climbers," said Rigoberto Uran, a compatriot of Bernal and another with a chance of victory having finished runner-up in the 2017 Tour to Froome.
Bernal impressed in last year's Tour in support of Thomas and Froome, but this year has been winning top races in his own right, most recently the Tour of Switzerland where teammate Thomas crashed heavily and had to pull out, adversely affecting his preparations for a successful defense of the title he won to such acclaim, particularly in his native Wales.
Earlier this year, in March, Bernal also took top honors in the prestigious Paris-Nice stage and has won plaudits from Tour de France organiser Christian Prudhomme, who told AFP: "It made one think what might come in the future, and now the future is coming, it's this July," he said.
It was fitting and perhaps an omen that Bernal was presented with his yellow jersey for winning Paris-Nice by the legendary Belgian Eddy Merckx, a five-time winner of the Tour de France.
The Tour's Grand Depart in Belgium is specifically to celebrate the 50th anniversary of Merckx's first Tour win in 1969 and his other incredible achievements, before it moves into France on day three.
Ahead of the riders will be one of the toughest routes in recent Tour history, with five mountain top summit finishes and a host of other testing climbs and hair-raising descents where the smallest error of judgment can lead to disaster.
Just about every meter of every major climb will be densely populated with fans, many donning the national flag and colors of their favorite rider or dressed in crazy costumes.
Hard core fans camp out for several days in advance to claim the prized viewing spots from where to cheer on the heroes of the peloton, some of the estimated 20 million people viewing the Tour from the roadside.
As they wait for their heroes to ride past, there is also the added attraction of the Tour caravan, a parade of vehicles, plugging various sponsors and giving out free gifts and promotional material to the onlooking watchers.
Towns and villages en route make a point of putting out the bunting to show off the best they can offer for the extensive coverage on French and international television.
The TV commentary often makes a point of highlighting the gastronomic delights the particular region has to offer, not to mention the variety of wine it is famous for, helping no doubt to boost tourism and local economies.
When the Tour started in 1903 it was for the original aim of boosting the circulation of the newspaper L'Auto, a forerunner to L'Equipe, and was an almost entirely all-French affair, which quickly grew into a national obsession.
The host country has provided the winner on a record 36 occasions, with Belgium, boosted by Merckx's efforts next best on 18, but riders from outside traditional European cycling countries have increasingly become a major factor in more recent Tours.
The success of British riders, with those six recent wins in Team Sky colors, has proved hard to stomach for many French sports fan and its media, hence the pressure on Bardet and Pinot to break that cycle this year.
The other dominant British cyclist has been Mark Cavendish, a specialist in winning the flat stages, which finish in daredevil bunch sprint at speeds of approximately 70 kph (43mph).
Cavendish has won 30 stages, four short of the record held by Merckx, but has been surprisingly left out of the Dimension Data squad for this year's Tour, leaving him "heartbroken" but vowing to return in the future.
Cavendish and the other sprinters such as Peter Sagan have no chance of winning the overall yellow jersey, but compete instead for the green jersey of points winner, based on placings on every stage and sprints at intermediate points on each stage.
Slovakian Sagan has won it six times and few would bet against him, but there are a clutch of other young hungry sprint specialists like Dutchman Dylan Groenewegen (Jumbo-Visma) who will be looking for Tour de France stage glory.
Groenewegen will find support from the waves of Orange-clad Dutch fans who make the pilgrimage to the Tour each year, disappointed no doubt by the absence of last year's overall runner-up Tom Dumoulin, who like Froome is sitting out the race due to the after effects of an injury sustained in a crash.
The other major category is for the polka dot jersey of best mountain climber, with points awarded for placings at the top of summits.
Another Frenchman, Julian Alaphilippe, who rides for the cycling's most dominant team in terms of race wins, Deceunicnck-QuickStep, is defending his King of the Mountains title this year and will likely challenge for victories on a number of stages.
Bastille Day showdown
Look for him in particular on Bastille Day, July 14, where a hilly leg finishes in Brioude, the home town of Bardet, who will also be keen to make an impression.
Whether Bardet, or another home rider, can break the overall stranglehold of the Team Ineos squad is another question, but that's not to rule out a clutch of other hopefuls, including Dane Jakob Fuglsang, who won the Criterium du Dauphine after Froome's untimely departure.
Bernal's more experienced fellow Colombian Nairo Quintana, part of a powerful Movistar squad which includes Mikel Landa and reigning world champion Alejandro Valverde of Spain, is a perennial contender, while British hopes outside of Thomas, rest with Adam Yates (Michelton-Scott), who was fourth in 2016.
"Anything can happen without Froome racing," 29-year-old Quintana told a press conference Thursday. "It's a bit special, more open, it'll be a much different Tour than usual.
"And Yates can launch his sudden attacks, but there are loads of guys who will fancy their chances without Froome around," added Quintana.
A total of 176 riders, in 22 teams of eight, will begin their quest for glory on Saturday, each with a specific task in the fast-moving and constantly changing peloton, which speeds around France at an average speed of over 40 kph (25 mph) for hour after hour, with just two rest days in over three weeks.
They will encounter extremes of weather from blistering heat to torrential rain, particularly in the high mountains at over 2,000 meters where the decisive battle for overall honors and the yellow jersey is set to be decided.
Despite the suffering and the sacrifice, the riders know that just taking part is a privilege afforded to an elite few and just finishing, whether in the Maillot Jaune or as the Lanterne Rouge, the last-placed rider, is an achievement to savor for their rest of their lives.
The next three weeks will see legends born, reputations enhanced or diminished, but like every previous Tour de France is guaranteed to be memorable.