SYDNEY, December 13 AAP - Matthew Hayden is virtually unstoppable.

The best Test batsman in the world overshadowed whirlwind opening partner Adam Gilchrist during a match-winning century stand that ensured Australia's seven-wicket victory over England in the limited overs tri-series clash at the SCG tonight.

Chasing England's gallant 8-251, Australia reached 3-252 with five overs to spare in front of a full house of almost 40,000.

Hayden stood tall with 98 from 92 balls, including eight fours and two sixes, following Gilchrist's energetic early contribution of 53 from 50.

"I told our boys in the dressing room they were going to come at us and we would have to hold our nerve - they played very well those two," said England captain Nasser Hussain.

If ever an innings deserved to reach three figures, it was Hayden's.

A mountain of runs over the last two years has made him the game's No.1 Test batsman - and his one-day status will soon be the same if he keeps this up.

The only man who can get Hayden out right now is Hayden.

It all looked so easy and risk-free until he fell to offspinner Ian Blackwell (2-38), gifting a catch to mid-on.

He tossed his head back, knowing a third international one-day century had gone begging.

"I guess it was pretty disappointing - obviously I thought the shot was on, I made good contact with it as well, but all in all it was a pretty disappointing way to end the innings," said Hayden.

"We've chased a lot of big totals over the last 12 months and it's always started from the momentum of the opening partnership.

"We're scoring up there at seven or eight runs an over.

"I guess I am throwing caution to the wind a little bit at the moment.

"I do think I'm putting pressure on sides though and that's an important factor in one-day cricket."

Hussain said of Hayden: "We've got to try to work him out. He's got that sort of arrogance that he's got nothing to lose, he's got so many runs under his belt he feels he can belt any ball anywhere.

"To have that sort of confidence must be a great thing."

The signs were good for Hayden right from the start.

He stroked a six over mid-wicket from Andy Caddick and then came up with a remarkable sweep shot from medium pacer Craig White that whistled to the boundary rope and ricocheted smack-bang into a spectator's forehead.

Gilchrist was the first to reach 50 from 44 balls with seven fours when Hayden was still on 45.

But Gilchrist had enjoyed most of the strike and he fell shortly after when he flicked a pitched-up ball from allrounder Ronnie Irani to mid-wicket.

Gilchrist was dynamic but Hayden hurtled along at an even more rapid rate, reaching his half-century from just 38 balls.

After captain Ricky Ponting's mid-week claim that Gilchrist would be ideal atop the order if he just showed the limited overs game a little more respect, the dashing left-hander blocked out the first over of the innings from James Kirtley.

That was as long as he wanted - or needed - to get his eye in.

By the time Australia reached 0-100 in 13.2 overs, England's respectable tally was looking totally inadequate.

Gilchrist's quick-fire knock showed exactly why Ponting wanted him to open with Hayden through to the fast-approaching World Cup rather than use another specialist opener.

Gilchrist might fail every now and again to a risky shot, but when he comes off the rewards for Australia are massive, especially when Hayden is in majestic touch alongside him like tonight.

Brett Lee was on a hat-trick in the final over of England's innings, but Caddick saw him out.

Lee finished with 4-47 from eight overs - successful but a bit expensive again.

Darren Lehmann's 10 overs of offspin netted 3-32 and he followed that up to be not out 27 with Damien Martyn (46 not out) when Australia cruised to victory.

The only Australian to disappoint was allrounder Shane Watson, who was hauled out of the attack with 0-25 from three overs.