Stately left-hander Matthew Hayden shrugged off a painful back injury to fashion a dazzling century as world champions Australia made undermanned Zimbabwe pay dearly for a major tactical blunder in the first cricket Test here Thursday.

Sent in by Zimbabwe skipper Heath Streak after he won the toss, the home country romped to 372 for three wickets on a pitch which played far more comfortably than Streak had expected when he made his big gamble.

Hayden has compiled a memorable 183 not out, which included a brutal 107 in the final session.

Skipper Steve Waugh, unbeaten with 61, is in sight of completing a century on the only major Australian ground on which he had not already reached three figures.

In the first Test in this country between the teams, Zimbabwe toiled manfully on the placid surface until the final session, but Australia are approaching a total which could shut their opponents out of the

game.

Hayden was forced to labour to complete his 15th century (13 fours, one five in five hours) in Test ranks, but ran riot immediately after reaching three figures.

His next 50 runs came in 35 minutes from 32 balls, with five more fours and three sixes.

Hayden was the spine of an Australian innings which frequently threatened to decimate the visitors' attack, but was unable to take full charge until the final hour.

He was hampered by a recurrence of a back injury which has plagued his career, and needed attention at the lunch and tea breaks.

Opening the innings, Hayden, 32 at the end of the month, held firm after losing his new-ball partner Justin Langer (26), Ricky Ponting (37) and Damien Martyn (53).

Hayden, in particular, and Waugh savaged the Zimbabwe attack late in the day, completing a 150 partnership in a lightning 127 minutes to put Australia in an almost unassailable position.

Early in the day, Langer departed after he and Hayden had crafted a breezy 43 in better than even time.

Langer, the senior partner in that

liaison, was unlucky to be dismissed after a purposeful 42 minutes -- an innings studded with five crisp boundaries, including several exquisitely timed cover drives.

The little left-hander fell in medium-pacer Sean Ervine's second over as he attempted to play a ball well outside off-stump.

Deceived by the bounce, Langer dragged the ball back in towards the stumps and was dismayed when the ball just flicked and removed his off bail.

Ponting survived only 12 minutes into the second session before Ervine struck again, trapping the right-hander in front with a faster ball.

Ponting's runs came from 65 balls in an hour and a half which netted him six thunderous boundaries.

Martyn (nine fours) looked to be in marvellous form, but lost his wicket when he played a rash shot to a delivery from spinner Trevor Gripper and was caught by Craig Wishart at first slip.

There were early warning signs for the Zimbabwe bowlers as Langer drove Streak's second ball of the match to the cover boundary.

Ervine, a 21-year-old mediumpacer playing in only his third Test, provided the one bright light for Zimbabwe, capturing 2-56 from 17 persistent overs.

SCOREBOARD

Scoreboard at the close of play on the opening day of the first test between Australia and Zimbabwe in Perth on Thursday:

AUSTRALIA: First innings

Langer b Ervine 26

Hayden not out 183

Ponting lbw b Ervine 37

Martyn c Wishart b Gripper 53

Waugh not out 61

Extras: (b-4, lb-4, w-1, nb-3) 12

Total: (For 3 wkts in 90 overs) 372 Fall of wickets: 1-43, 2-102, 3-199 To bat: Lehmann, Gilchrist, Bichel, Lee, Gillespie, MacGill

Bowler O M R W

Streak 18 6 82 0

Blignaut 20 3 74 0

Ervine 17 2 56 2

Price 22 5 94 0

Gripper 13 0 58 1

ZIMBABWE: Streak, Ebrahim,

Gripper, Vermeulen, Carlisle, Wishart, Taibu, Evans, Blignaut, Ervine, Price