Nairo Quintana retained the overall lead but, with the first four riders within 53 seconds of the Colombian, the three-week race is set for a dramatic finale.
Dumoulin remains in a strong position with the final day time trial on the cards, but Quintana has one more mountain stage – including the Monte Grappa – to try and open up the biggest possible lead.
Tejay Van Garderen clinched his maiden Grand Tour win on Stage 18 of the Giro d'Italia.
We all know the feeling, can't hold it, can't hold it...
The race resumes Tuesday with a 222 km 16th stage from Rovetta to Bormio.