Rosa put down two attacks in the final 1,500m, neither of which saw him gain an advantage on his rivals Esteban Chaves (Orica-BikeExchange) and Rigoberto Uran (Cannondale-Drapac).
The rider insisted he need to surprise the Colombian pair, but Martinelli believed the Italian should have stayed in their wheels until closer to the end.
“I’ve only been this upset a few times in my life,” sports director Giuseppe Martinelli told La Gazzetta dello Sport newspaper.
“If Rosa had listened to me, he would’ve won. You can’t throw away an occasion in that way. You can’t lose like that. I mean, you can lose, but not by miscalculating."
He added: "Diego should’ve not moved like he did. I told him. He should have stayed in the wheels, both on the Selvino and in Bergamo Alta without even considering what happened in the final.
“In the last curve, he should have been in second position regardless of who was in front. It was clear the other two would help each other, it happened in the Giro d’Italia already this year … And instead, he went through first. A close second place in a monument is nothing to laugh at, but this makes me feel truly sick.”
Rosa admitted after the race that his first attack was useless, but believed that he wouldn't have beaten Chaves or Uran in a straight-up sprint for the line.
“That attack at 1600 meters was useless. But I wasn’t the fastest and I had to play my hand, a surprise," he told press.
“I believed. I knew that Chaves was faster than me in a straight up sprint. I didn’t want to just lose stupidly. I knew that curve at 250 meters. Uran obviously closed the gap to me, but I don’t want to cause polemics. It happens, it’s normal. If I had made it through with two meters on them then it would’ve worked, instead, nothing.”
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