As he prepared to fly out with his team to South Africa on Thursday, Cook, who has never won a test series against the Proteas in his garlanded career, described just how important a victory be.
"It would mean a huge amount to beat the world number one nation in their backyard," the 30-year-old, leading the current fifth-ranked test nation, told a news conference. "That's the challenge we've got ahead of us.
"Reflecting back to Pakistan, there's something inside me saying we had an opportunity we couldn't quite take. I wonder if this is an opportunity I can take," Cook added, musing on the recent defeat in the United Arab Emirates.
"Losing 2-0 in the series hurts me quite a lot because I didn't think we were that far off. The result didn't seem a fair reflection of the tour. We definitely now have an opportunity."
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Cook believes the South Africans, who have just suffered a humbling 3-0 defeat on merciless turning pitches in India -- a loss which cut their lead in the ICC's world rankings -- are going through a period of transition.
"It's one side I haven't actually beaten in a series. They've had a bit of change," he said.
"When you lose greats of the game -- Graeme Smith, Jacques Kallis, (Makhaya) Ntini, (Mark) Boucher -- there's always going to be a bit of evolution in a side and trying to replace them is nigh on impossible, especially in one generation."
Cook, who led England to victory over Australia this year, admitted his team have not got a settled top seven but thinks that presents an opportunity for top-order batsmen like Nick Compton and Alex Hales.
Cook confirmed that the exciting Hales would get "first opportunity" to stake his claim to be his new opening partner but stopped short of guaranteeing he would play in the first of the four tests in Durban, starting on Boxing Day.
Of the axing of experienced batsman Ian Bell, Cook was reminded of his own feelings at being left out of England's World Cup squad this year.
"I remember how disappointing and gutting that was but those couple of months away from the firing line, from cricket and having time to be at home gave me a new lease of life," Cook said. "Hopefully, that can be the same for Ian."
(Writing by Ian Chadband, Editing by Ed Osmond)
