Some individual brilliance from Junee recruit Dakota Ruta was enough for the Diesels to score consecutive wins.
Junee led for less than three minutes but they did just enough to get past Kangaroos to take a 20-14 victory at Equex Centre on Sunday.
The Diesels five-eighth was brilliant, setting up their opening try after a big bust up the middle and then chipped ahead for himself to put a dagger through the heart of the Wagga side in the dying stages.
Diesels coach Trent Schubach couldn't be more pleased with the impact the Kiwi is having.
"He was the difference between the two sides," Schubach said. "He's getting better and better each week."
Junee let a plethora of chances slip in both halves but Kangaroos didn't make them pay and in the end it proved costly.
They were kept scoreless in the second half after Nick Trevaskis was denied what would have been the match winner in the final minute after a forward pass was ruled in the lead up.
Rusiate Kaliseiwaqa then run 90 metres to score after the siren off the resulting scrum.
Schubach was pleased with how his team scrambled.
"We blew a number of chances in the first half, just can't hold onto the ball at crucial times but we did a lot of tackling so it was a pretty good effort in the second half to keep them scoreless.
"We hustled around a fair bit to keep them out."
Kangaroos took the early ascendancy as Warren Lloyd crossed after five minutes for only the Diesels to respond when Ruta set up Ritchie Herangi five minutes later.
The Wagga side went back in front when Trevaskis scored and they kept their advantage when Cameron Andrews prevented a certain try.
The slender fullback was able to hold up Jarom Vakarewakobau in the in-goal when he looked an absolute certainly to score with seven left in the half.
Kangaroos took advantage and increased their lead to 14-6 when Lloyd went over for his second just before the break.
Vakarewakobau wasn't going to be denied for a second time when he cut the margin to four points with 20 minutes remaining.
Both sides had chances to add to their scores but it wasn't until the late four minutes that Ruta took control of the game.
Schubach's conversion gave Junee the lead and despite the late scare from Trevaskis they were able to hold on and move around Kangaroos in the process.
The Diesels are now fifth with three wins from their first six games but Schubach knows they will need to be a lot better in their clash against Gundagai next week.
Kangaroos also face a big task as they look to score their first win since round two up against Southcity.