Shane Warne and Andrew Strauss shared top billing with their private battle on day one of the 2005 Ashes decider at The Oval - but each of them identified a third man who may hold the key to the final Test.

Warne, whose ninth Ashes five-wicket haul stopped England making the most of winning an important toss, and home centurion Strauss were agreed on a hard and flat pitch the influence of Ashley Giles' spin is likely to be considerable as conditions begin to deteriorate.

It was only Warne's wealth of experience which helped him to figures of five for 118 on a largely unresponsive surface - but after Strauss had made a determined 129 in England's 319 for seven by stumps, it was the world's most prolific wicket-taker who was first to nominate Giles as a man set to play a significant role over the next four days.

Warne and Giles each cloaked their emphasis on the importance of Giles' bowling in a little mid-match psychology as they sought to claim the ascendancy in a Test Australia must win to retain the Ashes - and England need only draw to regain them.

"We have probably just got our noses in front," said Warne, whose team trail 2-1 and remain in danger of becoming the first set of Aussies to lose a series to England for 18 years.

"It will start spinning as the game goes on, and I think Ashley Giles will be a major player for England," he added.

Strauss, meanwhile, was talking up England's chances despite a disappointing first innings so far - given that the hosts won the toss and therefore the priceless right to bat first in ideal conditions.

"We just feel it is a little bit of a day-two wicket already - a little bit drier than usual for The Oval," suggested the left-handed opener, who hit 13 fours in his 150-ball hundred and shared an important fifth-wicket stand of 153 with Andrew Flintoff (72).

"That means it might break up a little bit towards the end of the match, helping Ashley Giles."

Strauss described his seventh Test hundred as perhaps his best so far, because it came in such an important match.

He and Warne each had praise for one another too, Strauss' glowing and his opponent's considerably more qualified.

"He has been awesome all series, and this time was no exception," the Middlesex batsman said of the great leg-spinner.

"It was not really turning for him, but he was getting the ball to skid through and hurry. It shows the bowler he is, and I think it was a fantastic effort.

"It gets a little bit easier when you have faced him a few times - the experience helps you. But every time you face him it is a massive challenge."

Warne was delighted with his own performance, conceding he had to call on all the expertise befitting a bowler with more than a decade of success against the world's best behind him.

"I would obviously prefer to be bowling in the second and fourth innings - but if you have to bowl on the first day you have to use your experience, mixing it up from over and round the wicket," said the veteran, who will be 36 next week.

"There is not much in the pitch, but you have to use subtle variations. One thing I have is experience - and I had to use a little bit of it this time.

"I was just trying everything I could to try to create some doubt for Strauss - because that is what I needed to do."

Warne congratulated Strauss on his determination in a hundred badly needed by England.

"I thought he played pretty well," he said. "He played and missed a lot. But he hung in there, and that is what both teams have done in this series. You have to give him credit."