Australian cyclist Nicole Frain involved in horror Tour de France Femmes crash, causing Marta Cavalli to withdraw

Australia's Nicole Frain appeared to cause a horror crash on day two of the Tour de France Femmes, which forced one of the race's stars, Marta Cavalli, to withdraw.

Frain, Australia's national champion, was rejoining the peloton at speed as she attempted to make up ground with around 25 kilometres to go on the stage from Meaux to Provins.

Several cyclists were already on the ground from a previous crash, which had significantly reduced the speed of the peloton.

Frain, who appeared not to notice the pile-up in front of her, careered into Cavalli, who landed heavily on her back and remained on the ground for several minutes.

The Italian eventually got up and continued to ride, but was soon pulled from the race and was left in tears.

Her team FDJ-SUEZ-Futuroscope later announced that she had been sent to hospital for monitoring with concussion.

Cavalli was runner-up at the Giro Donne — one of the biggest races in women's cycling — and one of the Tour's pre-race favourites.

On social media, 29-year-old Frain — who is riding with Parkhotel Valkenburg — apologised for the incident, saying she had not been aware of the crash before she approached the peloton.

"After working hard to come back to the peloton in the convoy and with my teammate, the speed we rejoined the pack would have matched their pace," Frain wrote.

"This meant I crashed overtop [sic] of the rider on the ground and I did my best to avoid it but I had nowhere I could go."

Frain was able to complete stage two, but said she was also left worse for wear.

"Today didn't go how I hoped," she wrote.

"It was hectic and I didn't feel comfortable all day.

"I'm sore as well and will monitor how I feel. I'm lucky I could get back on my bike."

Fellow Australian Amanda Spratt — who admitted to being emotional about the opportunity to ride in the Tour on day one — was also a victim of the crash.

The stage was ultimately won by Dutch champion Marianne Vos (Jumbo-Visma), who timed her sprint to the finish to perfection.

Vos broke away from a group of six to win the stage in five hours, seven minutes and 46 seconds.

The 35-year-old, a multiple world champion, now adds her first yellow jersey to her incredible career record.

Vos was a vocal advocate for the re-introduction of the Tour de France Femmes and finished second in the first stage on the Champs Élysées in Paris.