Dario Cataldo (Astana) claimed victory on stage 15 after spending more than 200km out front in the day's break, winning a sprint finish against Mattia Cattaneo (Androni Giocattoli-Sidermic).
It was a torrid day for Primož Roglič (Jumbo-Visma) who first ended up on a team-mate's bike, after a mechanical, before he crashed into a guard rail on a descent close to the finish line and lost 40 seconds to his GC rivals.
Vincenzo Nibali (Bahrain-Merida), as well as the other contenders for the overall, took full advantage of this, as they had attacked in the closing kilometres and took time out of Roglič.
Richard Carapaz (Movistar) finished in the GC group that included Nibali and Simon Yates (Mitchelton-Scott) to extend his overall lead.
During the stage, Cataldo and Cattaneo's advantage drifted out to 12 minutes at one point, with the peloton eventually limiting the gap, but lacked the need to fully bring them back into the fold, although the GC group eventually only finished half a minute down.
Stage 15 developed into two races, with the GC battle continuing behind. Simon Yates (Mitchelton-Scott) opened up proceedings with a failed attack at 46km to go, before Miguel Ángel López (Astana) also stretched his legs.
Primož Roglič (Jumbo-Visma) then had a mechanical with 18km remaining, losing time waiting for his team car and eventually taking team-mate Antwan Tolhoek's bike.
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Hugh Carthy (EF Education First) attacked with 13km to go, looking to get himself back into the top 10 on GC, with Yates then going again before Vincenzo Nibali took his chance with a big attack and breaking free of the group.
Pink jersey holder Richard Carapaz (Movistar) went with him, the pair soon catching Hugh Carthy and beginning to reel in Cataldo and Cattaneo.
Roglič then crashed on a descent, losing valuable time to his rivals, as they all finished half a minute behind Cataldo.
Carapaz remains in pink going into the rest day, 47 seconds ahead of Roglič and 1-47 ahead of Vincenzo Nibali.
How it happened
After two big days in the mountains, stage 15 was likely to offer some respite for the GC hopefuls, with a breakaway likely to succeed over a course similar to the autumnal Il Lombardia Monument.
Profile map of stage 15 of the Giro d'Italia 2019
Dario Cataldo (Astana) and Mattia Cattaneo (Androni Giocattoli-Sidermic) made the day's break, and had an advantage of over 10 minutes with 100km remaining, as the race sleepily made it's way along the flat.
The peloton showed little desire to bring the duo back in, with the GC teams opting to save their energy, with Jumbo-Visma eventually taking up the chase to limit the time lost to the leading two.
Domenico Pozzovivo and Damiano Caruso (Bahrain-Merida) then came to the front for team leader Vincenzo Nibali, with Primož Roglič placed near the back of the large GC group.
Simon Yates then attacked with 46km to go, with the majority of GC contenders following but Roglič late to react. Yates went again a kilometre later but was once again reeled in.
With 20km remaining, Joe Dombrowski (EF Education First) took a nasty tumble, that also brought down Ilnur Zakarin (Katusha-Alpecin).
Television pictures then cut to Primož Roglič who was behind the GC group, although not suspected to have been involved in the crash. The Slovenian was, however, riding team-mate Antwan Tolhoek's bike, and saw him 20 seconds behind with 18km to go.
Hugh Carthy (EF Education First) then attacked, looking to get himself back into the top 10 on GC, with Yates attacking again soon after with 13km to go as Roglič seemed to have gotten himself back into the group.
It was then Vincenzo Nibali's turn, hearing that Roglič may be struggling, he attacked with 11km to go, taking Richard Carapaz (Movistar) with him, as the other GC riders scrambled to grab their wheels. Roglič, however, couldn't follow.
Carapaz and Nibali then began riding together, both sandwiching Roglič on GC, one looking to extend their lead over the Jumbo-Visma rider the other looking to claw time back, soon catching Hugh Carthy to become the second group on the road.
Roglič, maybe taking too many risks when riding a team-mate's bike on a descent, crashed into a guard rail, but got back up and continued chasing.
The Nibali group were joined by Simon Yates, but had left it too late to bring Cataldo and Cattaneo back into the fold. The leading pair lined up for the sprint finish, with Dario Cataldo proving too much for his countryman, taking his first Giro d'Italia stage win since riding his first Italian Grand Tour in 2008.
Yates led the Nibali group across the line next, 11 seconds down, with Roglič then coming across the line 40 seconds later.
Richard Carapaz keeps the pink jersey going into the rest day, with his advantage over Roglič up to 47 seconds.
Results
Giro d’Italia 2019, stage 15: Ivrea to Como (232km)
1. Dario Cataldo (Ita) Astana, 5-48-15
2. Mattia Cattaneo (Ita) Androni Giacattoli-Sidermic, at same time
3. Simon Yates (GBr) Mitchelton-Scott, at 11 seconds
4. Hugh Carthy (GBr) EF Education First
5. Richard Carapaz (Ecu) Movistar
6. Vincenzo Nibali (Ita) Bahrain-Merida, all at same time
7. Miguel Ángel López (Col) Astana, at 36s
8. Rafal Majka (Pol) Bora-Hansgrohe
9. Domenico Pozzovivo (Ita) Bahrain-Merida
10. Mikel Landa (Esp) Movistar, all at same time
General classification after stage 15
1. Richard Carapaz (Ecu) Movistar, in 62-24-00
2. Primož Roglič (Slo) Jumbo-Visma, at 47 seconds
3. Vincenzo Nibali (Ita) Bahrain-Merida, at 1-47
4. Rafal Majka (Pol) Bora-Hansgrohe, at 2-35
5. Mikel Landa (Esp) Movistar, at 3-15
6. Bauke Mollema (Ned) Trek-Segafredo, at 3-38
7. Jan Polanc (Slo) UAE Team Emirates, at 4-12
8. Pavel Sivakov (Rus) Team Ineos, at 5-24
9. Simon Yates (GBr) Mitchelton-Scott, at 5-48
10. Miguel Ángel López (Col) Astana, at 5-55
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Jonny was Cycling Weekly's Weekend Editor until 2022.
I like writing offbeat features and eating too much bread when working out on the road at bike races.
Before joining Cycling Weekly I worked at The Tab and I've also written for Vice, Time Out, and worked freelance for The Telegraph (I know, but I needed the money at the time so let me live).
I also worked for ITV Cycling between 2011-2018 on their Tour de France and Vuelta a España coverage. Sometimes I'd be helping the producers make the programme and other times I'd be getting the lunches. Just in case you were wondering - Phil Liggett and Paul Sherwen had the same ham sandwich every day, it was great.
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