Re: 2019 Giro d'Italia stage 9: Riccione - San Marino 34.7km
I think Roglic beating Yates by 40 seconds would be about par.
Less than 20 seconds and Yates could become favourite. More than a minute and things start to look difficult for Yates. But there is a long, long way to go.
I think Lopez will go well. Nibali I am not so sure about.
Amongst the main riders, if I had to predict:
Roglic
Yates +40
Lopez +55
Nibali +1:10
One possibly underestimated thing about this parcours (the whole race, not this stage) is how much of a premium it puts on descending. And Roglic is a spectacular descender. If Yates/Lopez can get a gap on any climb that is not a mountaintop finish Roglic will likely bring them back.