Clarke and teammate Esteban Chaves both made it into the early, massive breakaway on stage 4, and when Matthews was dropped from the main group with 50 kilometres to go, the Australian and the Colombian stayed in contention in the leading break.
Clarke himself briefly lost contact on the final climb of Biassa with the leading break as it merged with the chasing group of GC contenders. But a gutsy descent enabled the 29-year-old to regain contact, taking second behind Davide Formolo - and a useful time bonus - that moved him into the overall lead.
“The best form of defence was attack, and with Esteban Chaves and myself in front, we had no need to be worried,” Clarke told reporters at a press conference.
“The gap went out to 10 minutes, I was not exactly sure what happened behind, but then someone chased us.”
Clarke and Chaves both stuck solidly in the leading break as they rode over the succession of smaller climbs and through La Spezia at the start of the final lap. But by that point, the Astana-driven bunch of less than two dozen riders was closing in and a different kind of battle was about to commence.
“Then on the last lap, we got information that they [the overall contenders' group) were coming back and coming fast,” said Clarke, who was dropped close to the summit of the third category ascent. “The idea was just to hope they wouldnt’ catch us too far from top of climb, although that was a very long 500 metres for me.
“I was a good 10 seconds behind and Astana and Tinkoff-Saxo were driving hard because they had dropped a few GC guys.
“I knew it would be super challenging getting back on, but when you know that all you got to do is catch that group and you’ve got the maglia, it gives you a bit of motivation.”
Like his teammate Michael Matthews, who lived in Italy in Varese with the Australian national team and who will be marrying in the same country after the Tour, Clarke’s links with Italy are very strong.
“For me, Italy has always been special”, the Australian - speaking in fluent Italian - told the press conference. “I lived here for four or five years, my first pro team [in 2008] was Amica Chips, an Italian squad and I’ve ridden races here for so many years.
“This year I finally got into the line-up to race in the Giro d’Italia for the first time, I specifically asked my director if I could do this race, and I want to do the best I can now to defend the jersey.”
The winner of the Herald Sun Tour in 2014, Clarke’s previous big win in Europe came when he outgunned Tony Martin (Etixx-QuickStep) at the summit of the Valderazcay climb in the 2012 Vuelta a España. He ended up wearing the King of the Mountains jersey all the way to Madrid. In the Vuelta, Clarke had deliberately lost time on the previous stages to ensure he was not a general classification threat - but this time, taking the pink in La Spezia, he had fought tooth and nail to stay in contention throughout.
The question of how long Clarke can hold the jersey is an obvious one, particularly with a mountaintop ascent to Abetone less than 24 hours away. “I’ll be just happy to ride in tomorrow, to be honest,” Clarke told Cyclingnews.
“It’s a very hard climb, 17 kilometres, but look, we’ve got Chaves in second place [on GC] and he can go uphill very fast. I’m confident that between him and myself we can hold it for a couple more days.”
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