The race director of the Giro d'Italia says that critics should judge the race after it finishes, rather than by its start-list.
Alberto Contador (Tinkoff-Saxo) stands out among the 198 cyclists ready to roll off in Liguria on Saturday. He counts six Grand Tour wins in his palmarés, including the Giro in 2008 and the Tour in 2007 and 2009.
Sky's hopes for overall victory in the three-week race rest with Australian Richie Porte, who has won nearly every race he has entered so far this season.
"It's normal to ask why they race the Tour or try to salvage their season in the Vuelta a España," Vegni told Cycling Weekly.
"It frustrates me somewhat, but we don't have anything to be jealous about compared to any other race. The Vuelta had all the big names last year, but I don't want them to come to my race after having gone poorly at the Tour de France."
Besides Contador and Porte, possible Giro winners this year include Colombian Rigoberto Urán (Etixx-Quick Step) and Italian Fabio Aru (Astana).
Aru's Astana team-mate, Nibali, won the Giro in 2013 but chose to focus on the Tour in 2014. This year Astana gave him the green light to skip the Giro again and aim for another Tour title.
"The only thing that bothers me, if you can say bother, is Vincenzo's absence. He's Italian and he's won the Tour. Of course, he says that he wants to defend the Tour title and then there are those who say that he won the Tour due to circumstances last year," Vegni said.
"I understand his motivation. He wants to show that he's the strongest and that he can win again. Clearly, though, I would've like to have him here."
Nibali's victory in the Tour last year was arguably tarnished by two of his biggest rivals, Froome and Contador, crashing and abandoning the race in the first week.
With fewer time trial kilometres, the 2015 Tour appears even more suited to Nibali. The Giro, on the other hand, features a long 59.4-kilometre time trial in the second half of the race.
"Froome could've have done a lot with the time trial in the Giro," added Vegni. "In the Tour, without a big TT…? It's hard to say until the race is over. Everyone criticised Nibali, but then he won the Tour."
As leading riders opt to skip Italy in favour of France, Vegni says that this allows the Giro to make new stars instead.
"They said that it was bad last year. Nibali decided to race the Tour, Contador didn't come, others didn't come," Vegni added.
"We had Quintana and many young riders. Afterwards, we see Quintana win the Giro. That win prompted everyone to say that he can win the Tour. So if he goes to the Tour, then he's a star? He was a star already in the Giro."
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