England were looking resigned to another heavy defeat and struggling to stop Australia's march to victory and a 4-0 series lead in Melbourne on Sunday. The tourists looked deflated after skipper Alastair Cook dropped two catches as England searched for early breakthroughs to put pressure on the Australians, who were chasing 201 runs on the fourth day to win the fourth Ashes Test. The two fielding blunders from the captain were psychological body blows for England and evidence of batsman Kevin Pietersen's comments on Saturday in a television interview that the tourists were "mentally fragile". Australia clinched the Ashes inside 14 playing days with huge Test wins in Brisbane, Adelaide and Perth, and England appeared incapable of preventing Michael Clarke's team from taking a 4-0 series lead ahead of the fifth and final Test in Sydney later this week. At lunch, Australia were doing it easy at 143 for one, just 88 runs from victory with Chris Rogers unbeaten on 81 and Shane Watson not out 36. Cook got his right hand to a snick from Rogers on 19 through slips after wicketkeeper Jonny Bairstow failed to respond, and then the England captain dropped a straightforward two-handed chance from David Warner (22) off Stuart Broad. Warner scored only three more runs before he was caught behind off Ben Stokes and Australia's first wicket came down at 64. Rogers went on to score his fourth half-century of the series on the ground where he plays for Victoria in the Sheffield Shield competition. Left-hander Rogers has now scored two half-centuries in the Melbourne Test and is chasing his second Test century after scoring 110 against England in the last series earlier this year at Durham. Australia's surge to apparent victory comes after a dramatic turnaround in fortunes on Saturday's third day when England, holding a 51 innings lead, were bowled out for 179, leaving the home side 231 runs to win the Test. Symbolic of England's malaise, Cook did not bring on his specialist spinner Monty Panesar until 90 minutes into the fourth day and he had little effect on stemming the Australian run flow, with his four overs going for 21 runs. Source: AFP