After initiating an early attack, Sam Bennett (Bora-Hansgrohe) held on to finish third after Jakub Mareczko (Wilier Triestina).
Finishing in the peloton, Jungels said he would aim to keep the jersey until Sunday.
“It was fantastic today, it was a great stage.
“The final was a little tricky, there were a lot of ambitious riders up front and a bit of a fight by the GC riders to stay up front,” he said.
“We showed the team was there all day and I’m happy we finished it off again.”
After winning his second stage, his young teammate Gaviria has made history as one of only two riders in the 21st century to have won two or more stages before turning 23.
His victory means he will wear the red maglia ciclamino which is awarded for the points classification.
Top ten results
|1.||Fernando Gaviria - Quick-Step Floors||3:40:11|
|2.||Jakub Mareczko - Wilier Triestina||"|
|3.||Sam Bennett - Bora-Hansgrohe||"|
|4.||André Greipel - Lotto Soudal||"|
|5.||Phil Bauhaus - Team Sunweb||"|
|6.||Kristian Sbaragli - Dimension Data||"|
|7.||Ryan Gibbons - Dimension Data||"|
|8.||Roberto Ferrari - UAE Team Emirates||"|
|9.||Jasper Stuyven - Trek-Segafredo||"|
|10.||Enrico Battaglin - Team LottoNl-Jumbo||"|
|1.||Bob Jungels - Quick-Step Floors||23:22:07|
|2.||Geraint Thomas - Team Sky||+06|
|3.||Adam Yates - Orica-Scott||+10|
|4.||Domenico Pozzovivo - AG2R La Mondiale||"|
|5.||Vincenzo Nibali - Bahrain-Merida||"|
|6.||Tom Dumoulin - Team Sunweb||"|
|7.||Nairo Quintana - Movistar Team||"|
|8.||Bauke Mollema - Trek-Segafredo||"|
|9.||Tejay Van Garderen - BMC Racing Team||"|
|10.||Andrey Amador - Movistar Team||"|