Image 1 of 4 Fabio Aru (Astana) can pull a wheelie just as good as Peter Sagan (Image credit: Bettini Photo) Image 2 of 4 Fabio Aru (Astana) (Image credit: Tim de Waele/TDWSport.com) Image 3 of 4 A sun-safe Greg Henderson signs in 2013 (Image credit: Tim de Waele/TDWSport.com) Image 4 of 4 Fabio Aru (Astana) (Image credit: Bettini Photo)

Fabio Aru is considering legal action against Lotto Soudal rider Greg Henderson after the Australian accused Aru of being caught up in a UCI Biological Passport case.

Related Articles Aru illness prompts speculation that Nibali could ride Giro d'Italia

The Italian, who is set to ride the Giro d’Italia next month, pulled out of the Giro del Trentino, citing illness for his non-participation in the four-day Italian stage race.

Last night Henderson took to Twitter, just hours after the UCI Licence Commission confirmed that the Astana team could keep its WorldTour licence. He wrote: “Sad to see @fabaro1 "sick". Mate make sure next time u come back to our sport "healthy". Aka. Clean! #biopassport! Or don't come back!”

He followed that up by posting: “I am so sick of it. It becomes common knowledge within days. Why try cheat.”

Henderson has close to 40,000 followers on Twitter.

At the start of stage 3 of the Giro del Trentino, Paolo Slongo, Astana’s head coach at the race, questioned the validity of Henderson’s comments, as well as denied knowledge of Aru being the subject of a UCI Biological Passport case.

“We don’t know anything about it. As far as I know I think it’s just someone firing off. It’s strange... I think he’s come up with a different interpretation to the stomach problems that he (Fabio) had. As far as I know the reality of things are different.”

The open accusation of doping could lead to legal action against Henderson, who was quick to apologise this morning on Twitter.

“When you are sick. You are sick. Jumping to conclusions helps nobody. My mistake @FabioAru1. I should shut my mouth. Sincere apologies.”

Cyclingnews spoke to Henderson, who explained, “It was just me jumping to conclusions and I can’t do that. It’s ridiculous. It does the sport no good and I’ll speak to his manager and apologise. The information came from sources and it got me angry at the time. It was an angry and unsubstantiated Tweet, that’s exactly what it was.”

Slongo could only speculate as to whether Aru would take action against Henderson for his accusations. “I think he’ll take some kind of personal action against whoever said it or tweeted it.

“You need to ask him. For sure it’s not a nice thing to happen. I’m sure he’ll distance himself from the accusations. Unfortunately our world is like this. Is this Greg Henderson guy part of the UCI Biological Passport panel?”

Aru’s agent Alex Carera told Cyclingnews that the Astana rider is considering legal action. Carera also said that as far as he knew, Aru was not involved in a UCI Biological Passport case.

“A famous athlete like Greg Henderson, who has 30,000 followers on Twitter, can cause huge damage to a person like Fabio, his Astana team and the sport, in this way,” Carera told Cyclingnews.

“Our lawyers will look at what has happened and consider where to start legal action. Fabio Aru’s image has been damaged, he doesn’t deserve this. I hope the UCI will also take action against Henderson. He should be fined for what he’s done.”

Biological Passport cases are opened by the UCI if a rider shows suspicious readings in his blood profiles. Riders with such values are sent letters from the UCI asking them to explain any questionable readings before a case can be formally opened.

For now the matter seems to be confined to Twitter. Aru’s team captain Vincenzo Nibali posted a message saying, “It’s too easy to say sorry afterwards!! You’ve got to sue for damages!!!”

Fabio Aru retweeted a message by the Ciclismo2014 that reads: “The tweet by Greg Henderson against @FabioAru1 is SHAMEFUL. Lets hope the Astana team or someone else takes action, including legal action."