Kennaugh leads fellow Briton Froome by seven seconds in the overall standings after the Team Sky pair dominated the first stage which started and finished in Healesville.
"It's really a nice feeling being able to give something back to Peter Kennaugh," Froome, making his first race appearance in potentially the biggest season of his career, told reporters after completing the 126 km stage.
"The number of times he's emptied himself for me out on the road, he's been part of both my Tour de France victories. It feels nice to do something for him now," the 30-year-old said.
Froome, who has set his sights on double Olympic gold and a third Tour de France title, broke away on the Mt Saint Leonard climb and was joined by his team mate with barely 20 km to go as they took complete control of the race.
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"Massive thanks to the team and especially to Froomey because, once I got across to him, I pretty much just sat on his wheel the whole way up the climb," Kennaugh, who won the Great Ocean Road Race in Geelong on Sunday, said.
"Then once I got over, I was able to do some good turns and take it to the finish with him."
The second leg of the four-stage race is a 144-km run from Yarra Glen to Moe on Friday.
(Reporting by Amlan Chakraborty in New Delhi; Editing by John O'Brien)
