England centurion Matt Prior relished the "very special feeling" of his first Ashes hundred as he helped his side to the verge of their first outright series win in Australia in 24 years on the fourth day of the final Test.

Prior's 118 added to earlier hundreds from Alastair Cook and Ian Bell saw England to 644 all out - their highest ever total Down Under and enough to tee up what will surely be a third innings victory, and a 3-1 series win, on the final day.

They ended three wickets short on the fourth evening after reducing Australia to 213 for seven on the back of a 364-run first-innings deficit.

"It's a very special feeling," the England wicketkeeper told Sky Sports 1. "I was batting with Jonathan Trott in Melbourne when he got his and he came to me in the middle and said 'It's the best feeling in cricket' and I'd have to agree, an Ashes ton is very, very special and I'll treasure it."

Prior's 118 came in just 130 balls and he admitted he benefited from letting himself off the leash.

"It was time to take the initiative and be more attacking and ride your luck and see where you get to," he said.

Asked to explain his much-improved batting figures over the course of the series, Prior said: "Luck, I reckon.

"I started off with not much luck and ended up with a whole lot of it. Sometimes it's just not your day, sometimes it is.

"I've said the whole series I've been playing well and feeling good in the nets, and just needed a few things to go my way. Fortunately they have, towards the end of the tour."