The two late escapees spoiled the planned party for the sprinters after they got away on the first of seven closing circuits in Milan.
"We were always going to try," said Orica-GreenEdge sport director Matt White. "We tried, and it very nearly came off."
The combination of Keisse, an experienced six-day racer on the track, and Durbridge, a time trial specialist, was well-suited to hold off a peloton that initially had trouble deciding who should commit to the chase, then was plagued by punctures and mechanicals.
"We knew the circuit was tight and that it would be hard to organise a chase and there was also a few things that went in our favour in terms of certain guys puncturing and the like," White said.
"As I always say, it's one thing to have goals and another thing to have the team to be able to achieve them. But to have the Giro we have had, two years in a row, is very satisfying and all of the guys should be very proud."
Orica-GreenEdge leaves this year's Giro having scored two stage wins, three podiums and four days in the maglia rosa. The team scored their first success during the opening team time trial in San Remo, with Simon Gerrans crossing the line first and earning the first pink jersey of the race.
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Michael Matthews was the next rider to take the jersey after he finished second during stage 2. Matthews won stage 3 in the jersey, but then surrendered it the next day to teammate Simon Clarke, who finished second behind solo winner Davide Formolo (Cannondale-Garmin) during stage 4.
"People feel pressure when they don't think they can achieve the end goal," White said. "When you are confident in the working group, confident in each other and confident in the work you have done that is a different type of pressure and something our team can handle.
"We know what we are capable of doing," White said. "We can't win the Tour de France at the moment, we can't win the Giro d'Italia at the moment, but what we can win is certain targets, and that is a real strength of our team and our athletes."
