The Clarke-led Australia side won the fifth and final Test at the Sydney Cricket Ground (SCG) by 281 runs becoming only the third squad in the history of the game to complete an Ashes whitewash.
"It's an extremely special occasion. We couldn't foresee 5-0 after the England series but I said then the work we were putting in behind the scenes we were going to get the rewards," said Clarke after the match.
"The bowlers have done a fantastic job, I told them before the Test that they were the best attack in the world and I think they've earned that mantle," added Clarke before getting his hands on the Waterford Crystal Ashes trophy.
Clarke's counterpart Alastair Cook admitted that England were not good enough.
"It's obviously tough knowing that you've been beaten badly in five games. We weren't good enough to turn it around. We tried to change the way we played but anything we threw at Australia, they were good enough. When you hit rock bottom the only way is up. We know we have a huge amount of talent in England and we have to look about where we go from here," said Cook.