What a grand Grand Tour this year’s Giro is proving to be!

The breakaway, which caught No. 1 Alexander Vinokourov and No. 2 Cadel Evans watching each other instead of the split group, put given-up-for-dead contenders Bradley Wiggins (Team Sky) and Carlos Sastre (Candil) back in the hunt. Especially given the punishing mountain stages ahead, the Giro officially is a wide open race again.

Sastre took third, behind Russian Evgeny Petrov (Katusha) and Quick Step’s Darlo Cataldo. Petrov took the stage with a dramatic sprint on the final uphill section of the stage. Overall the lead group had nearly 13 minutes on the race leaders at the start of the day.

So now Riche Porte of Saxo Bank is the race leader, by a stunning margin over Vinokourov and Evans, who trail by 10 and 11 minutes respectively. Oh and a headline Vino would like to have back: “Alexander Vinokourov Growing More Confident by the Day of Giro d’Italia Success.” Ouch!

One can only wonder how the two leaders let top-caliber riders in a huge pack take off without them. This isn’t a matter of fitness or capability, it’s simple on-road intelligence.

You know that if the greats of the past were in a similar situation, all the way from Eddy Merckx to Bernard Hinault to Greg Lemond, there’s no way a former Tour de France winner and top contender in last year’s Tour would’ve been allowed to slip off the front.

Heck, if Lance Armstrong were in this year’s Giro, there’s no way it would have happened.

But there you have it. Inexplicable things happen in bicycle racing, and today’s stage will be remembered for a long time as one of those crazy strategic brain cramps that — if it costs Vino and Evans a shot at winning the Giro — prove anything can happen, even in the controlled environment of Grand Tour racing.

VeloNews and CyclingNews will have full results as they emerge.