Jonas Vingegaard and Remco Evenepoel face a race against time to be ready for the Tour de France after breaking bones in a crash in the Tour of the Basque Country.

Vingegaard, the double defending champion, and Evenepoel, the 2022 Spanish Vuelta winner, had their preparations for the Tour turned upside down in a split second on a Basque mountainside on Thursday.

The Tour, which starts on 29 June in Florence, has been billed as the battle of cycling's 'Fantastic Four'.

A third member of that quartet, Primoz Roglic, was also among the fallers as a dozen riders slid off on a downhill corner, some of them landing in a roadside ditch.

Roglic, a Slovenian, escaped with cuts and bruises after his second crash in two days. Vingegaard and Evenepoel both collected multiple fractures.

The Dane suffered rib and collarbone fractures and lung damage. Evenepoel, a Belgian, broke his collarbone and shoulder blade.

The fourth fantastic star, Tadej Pogacar a double Tour de France winner, is not racing in the Basque countryside as he trains for a Giro d'Italia-Tour de France double.

The Slovenian sent his best wishes for a speedy recovery to his "peloton mates".

A year ago, Pogacar entered the Tour de France barely recovered from a fractured wrist following a crash at Liege-Bastogne-Liege at the end of April. He stayed in contention for a fortnight, but then slumped, partly due to a lack of basic preparation.

Vingegaard and Evenepoel face the same challenge.

"It's too early to say, we'll have to wait days or even weeks before saying anything about the Tour," Frans Maassen, the Dane's sporting director at Visma-Lease a bike, said on Friday.

He said the two-time Tour winner had "had a very good night".

"Of course he's in pain, but his legs and head are fine. We dare to look ahead, said Maasen, adding that it could have been "much worse".

Evenepoel was heading back to Belgium on Friday for further tests.

"Given the circumstances, it's okay. His participation in the Tour should not be in danger", said Klaas Lodewyck, sporting director of Evenepoel's Soudal-Quick Step team.

Evenepoel sent out a video on Thursday evening.

'Mental scars' Ahead Of 2024 Tour de France

It means he is certain to miss Liege-Bastogne-Liege, which he has won the last two years, and the Amstel Gold one-day classics in April.

"He's disappointed. The Amstel Gold and Liege-Bastogne-Liege were two big objectives for him," said Lodewyck.

While some riders can recover and work themselves into racing shape faster, it generally takes eight to ten weeks.

That time frame suggests Vingegaard and Evenepoel could return for the Criterium du Dauphine at the beginning of June, a week-long event which traditionally serves as a dress rehearsal for the Tour.

But their preparations have been disrupted and the full physical and psychological toll will not be clear for a while.

"When you fall, there are physical injuries but there are also, and above all, mental scars," wrote former French rider Pierre Rolland on X on Friday.

"I'm not ashamed to say that after my last big crash at the Tour de France in 2016, the rest of my career was synonymous with apprehension and anxiety."

A week ago, French star Julian Alaphilippe said he was "much more apprehensive" since he hit a tree at Liege-Bastogne-Liege in 2022.

"It's a cruel sport, which demands a lot of sacrifice and where everything can fall apart at a stroke", he said.