* Armstrong crashes on first stage of Vuelta Castilla
* Astana team says American may need surgery
* Rider casts doubt on participation in May's Giro
(Adds Armstrong, Contador quotes, details on race)
By Iain Rogers
MADRID, March 23 - Seven-times Tour de France
winner Lance Armstrong fractured his right collarbone in a crash
during a race on Monday, throwing his plans to ride in May's
Giro d'Italia into doubt.
The American's Astana team said he might require surgery on
the injury sustained during the first stage of Spain's Vuelta
Castilla y Leon.
"I am very disappointed, especially for the Giro," the
37-year-old said when asked whether his participation in the
Italian stage race was in jeopardy.
In comments released in a team statement, Armstrong added:
"Now I feel miserable ... I hope I can tell you more about the
Giro in a week."
The Italian three-week stage race, which Armstrong has never
taken part in, starts on May 9 in Venice.
Armstrong was in obvious pain as he was helped into an
ambulance and taken to hospital after the incident involving a
group of riders with around 20 km left of the 168.3-km leg
between Paredes de Nava and Baltanas.
He was taken to the University Clinic in nearby Valladolid
for treatment and was later discharged.
Astana team boss Johan Bruyneel said the fracture had been
clean and the rider's recovery should be fast, although he gave
no timeframe.
"Armstrong will return home to the States to make a decision
on surgery options," the Astana statement said.
The rider said he had been lucky to have avoided one of the
sport's most common injuries for so long and that the only thing
he could do now was rest.
"This never happened in 17 years of pro cycling. That's
cycling. It's nobody's fault," he said. "The most important
thing for me right now is to get back home and rest up and begin
my rehab."
FRUSTRATED PLANS
The Vuelta was being closely scrutinised as it was the first
and only time Armstrong had been due to race alongside Spanish
team mate Alberto Contador before July's Tour de France.
Contador, the world's best stage-race rider, won the Tour in
2007 and there has been speculation about which of the pair
would establish himself as Astana's number one.
The Spaniard finished in 27th place in Monday's stage, which
was won by Joaquin Sobrino of the Burgos Monumental team, and he
said the accident had frustrated Astana's plans.
"It was a good opportunity to work together at a race," he
said in a statement. "Now only I can support him and wish him to
recover as soon as possible."
David Vitoria of Rock Racing took second place on Monday and
Jose Joaquin Rojas of Caisse d'Epargne third.
"I don't know how the crash happened because it was in the
middle of the peloton," stage winner Sobrino said.
"That it was Armstrong is a shame for us given all the media
attention he has attracted but it was nice anyway that he was in
the race today."
(additional reporting by Julien Pretot in Paris)
(Editing by Sonia Oxley)