It was the 29-year-old Spaniard's first Grand Tour stage win and Movistar's first at this year's Giro - still led by Jungels, with Geraint Thomas second.
Thomas' Team Sky team-mate Mikel Landa's late attack was caught as time gaps in the top 10 stayed the same.
Thomas is six seconds behind Jungels, with fellow Briton Adam Yates third.
Orica-Scott rider Yates is 10 seconds behind Quick-Step's Jungels, on the same time as favourites Nairo Quintana and Vincenzo Nibali, who also finished safely in the main bunch on Saturday.
Landa had built up a lead of 15 seconds on Jungels - a gap that would have seen him climb into the overall lead - before being reeled back by the peloton on the up-and-down finish into Peschici.
Sunday's stage takes the riders into the high mountains for the first time since stage four, with a summit finish on the category-one Blockhaus ending a relatively flat 149km from Montenero di Bisaccia.
1.  Gorka Izagirre (Spa/Movistar) 4hrs 24mins 59secs
2.  Giovanni Visconti (Ita/Bahrain) +5secs
3.  Luis Leon Sanchez (Spa/Astana) +10secs
4.  Enrico Battaglin (Ita/LottoNL) +12secs
5.  Michael Woods (Can/Cannondale) Same time
6.  Thibaut Pinot (Fra/FDJ)
7.  Vincenzo Nibali (Ita/Bahrain)
8.  Adam Yates (GB/Orica)
9.  Steven Kruijswijk (Ned/LottoNL)
10. Bob Jungels (Lux/Quick-Step)
1. Bob Jungels (Lux/Quick-Step) 38hrs 21mins 18secs
2. Geraint Thomas (GB/Team Sky) +6secs
3. Adam Yates (GB/Orica) +10secs
4.  Vincenzo Nibali (Ita/Bahrain) Same time
5. Domenico Pozzovivo (Ita/AG2R)
6. Tom Dumoulin (Ned/Sunweb)
7. Nairo Quintana (Col/Movistar)
8. Bauke Mollema (Ned/Trek)
9. Andrey Amador (Crc/ Movistar)
10. Thibaut Pinot (Fra/FDJ)
Gorka Izagirre emerged strongest from a breakaway group to claim victory on stage eight of the Giro d'Italia as Bob Jungels retained his overall lead.