LEEDS: Marcus North's second century of this Ashes series ensured Australia maintained their iron grip on the fourth Test against England at Headingley here on Saturday.

Australia, at tea on the second day, had been bowled out for 445 - a lead of 343 - after England collapsed Friday to 102 all out in their first innings.

North was last man out for 110, holing out to give pace bowler Stuart Broad his Test-best figures of six wickets for 91 runs in 25.1 overs.

That surpassed Broad's previous best of five for 85 against the West Indies at Kingston in February but the bowler's lack of celebration spoke volumes about the match position.

Western Australia left-hander North, out for 96 in the drawn third Test at Edgbaston, reached his third century in six Tests in grand style by sweeping off-spinner Graeme Swann for six to reach the landmark in 193 balls, including 12 fours.

Such was Australia's command, as they looked to level the seried at 1-1, that even Stuart Clark drove Swann for six and later twice pulled Broad high over square leg for two sixes in as many balls.

Broad did though take five of the six wickets to fall in the second session after Australia resumed on their lunch score of 306 for five.

Mitchell Johnson, who helped North add 70, holed out to Ravi Bopara at deep mid-wicket and three balls later Peter Siddle was clean bowled for a duck to leave Australia 394 for eight.

Broad eventually had the satisfaction of dismissing Clark but not before the tailender had made 32 off 22 balls featuring those three sixes.

England paceman James Anderson, who sustained a hamstring injury while batting Friday, didn't bowl at all between lunch and tea.

England took the new ball as soon as it was available with Australia 323 for five off 80 overs.

Two balls later England had a wicket when Brad Haddin, cramped trying to pull a bouncer from recalled fast bowler Stephen Harmison that was too quick for him, skied to Ian Bell at short backward square leg.

But North, who shared a fifth-wicket stand of 152 with Michael Clarke, then moved into the 80s with a flashing square-cut off Broad.

Australia resumed Saturday on 196 for four, a lead of 94, with Clarke 34 not out and North seven not out.

North set the tone when, off Saturday's first ball, he punched Anderson through the covers for four off the backfoot.

Harmison saw his first ball of the day - a short half-tracker - pulled so far in front of square by Clarke the ball went for four to long-on.

England were failing to follow the example of Clark, who'd shown how to bowl on a fine pitch for batting Friday by maintaining a probing line and length.

Broad then became the third England bowler whose first ball Saturday went for four when North clipped him off his legs

Australia vice-captain Clarke, who made 136 in England's second Test win at Lord's and 103 at Edgbaston, fell in sight of a third hundred in as many Tests when he was lbw to Graham Onions for 93, having faced 138 balls with 13 fours.