Bennett has finished comfortably in the peloton in 30th position on the stage for the sprinters, a stage won by his namesake - Ireland's Sam Bennett, who claimed his first victory of 2018, and his first stage win in a grand tour.
George Bennett underwent his first real test at the Giro d'Italia this morning, and he has passed with flying colours.
That saw Yates seize a 16-second advantage over defending champion Tom Dumoulin in the general classification, with Chaves moving up to third.
In the General standings substantial rearrangements did not happen - the second day in a row the pink Jersey was retained by the representative of "Mitchelton-Scott" Simon Yates.
After a gruelling final climb along a 150m stretch of road, Aru crossed the line - under the shadow of the Etna Astrophysical Observatory - with the main peloton, just 26 seconds behind race victor Johan Eseban Chavez (Mitchelton Scott).
This came after two thirds in the first week of this year's edition and a string of seconds and thirds in last year's race.More news: Sex Scandal: R. Kelly's Songs Removed From Spotify's Playlists
With a broken down ferry meaning that some riders were forced to spend five hours sat on the team bus getting to their hotels after Thursday's Mount Etna stage, today - at least until the final 15km - provided exactly the sort of easy day that they would have hoped for. 'There was a little bit of a gap, so I took the chance.
"I still have some work to do, but I was actually pretty happy with my climb today", Dennis said later.
Viviani had looked on course to take his third stage win of the race after taking the lead with the line in sight, but the Quick-Step Floors rider had to settle for second place on the same time.
"I feel relieved. I have been close so many times before in the Giro", said the Bora-Hansgrohe rider.
Four-time Tour de France victor Froome was in eighth place, 1 minute, 10 seconds behind.
Britain's Simon Yates held on to the overall lead by finishing in the group behind Bennett.