The Slovenian now leads the race over Gidich by four seconds after earning bonus points on the line.
“The team did a great job for me," Kump said. "Especially Rogina who put me in the ideal position.
"I may have started 50 metres too early but I believed I could win."
Kump's team mate Dušan Rajović grabbed the maximum points out on the road in the sprint classification and as a result sits third overall.
Behind him at the second sprint in Kutjevo, Adam Yates (Mitchelton-Scott) and Matej Mohorič (Bahrain Merida) fought for the scraps, both with one eye on overall victory in Zagreb. Mohorič won this round however, and now sits fifth overall at eight seconds, with Yates just one second behind (7th overall).
Early in the stage, Bahrain Merida put the peloton into the hurt box trying to force a split in the crosswinds some 160kms from the finish. Main GC rival Yates' team Mitchelton-Scott hung tough to eventually bring fast man Alex Edmondson to the fore for the bunch finale.
“Both James (Fouche) and Barnie (Peak) rode the front for majority of the day with Callum (Scotson) helping as well," Edmondson said.
“Coming into the finishing circuits it was really hectic with a lot of corners. I managed to surf around and ended up coming from a long way back from the last corner.
“It’s my first real opportunity to go for a gallop for a while so it was nice to be up there and it’s given me confidence for the next couple of days. The boys did an awesome job for me today; on to tomorrow.”
The worst affected by the split was Israel Cycling Academy, who brought back Ben Hermans, but lost Roy Goldstein and Australia's Freddy Ovett.
The day's escapee artists Alexis Guerin (Delko Marseille), Austrian Florian Kierner (Felbermayr Simplon Wels) and German Tobias Nolde (P&S Metalltechnik) didn't pull clear until halfway through the stage and after the first KOM atop Gradac Našički won by Austrian Markus Wildauer (Tirol KTM). Their lead and numbers slowly dwindled until just Nolde remained, swallowed up by the peloton four kilometres from the line.
The CRO Race continues tonight with the second stage, 183kms from Slunj to Zadar, streaming live on our site or via SBS On Demand from 11pm AEST.
How the Australians fared
5 Alex Edmondson (Mitchelton-Scott) ,,
21 Heinrich Haussler (Bahrain Merida) ,,
37 Nathan Earle (Israel Cycling Academy) ,,
62 Benjamin Hill (Ljubljana Gusto Santic) ,,
100 Timothy Guy (Ljubljana Gusto Santic) 0:26
105 Callum Scotson (Mitchelton-Scott) 1:39
DNF Freddy Ovett (Isral Cycling Academy)