Captain Alastair Cook must exert more authority over his England team or face a 5-0 Ashes humiliation, says Shane Warne.
Cook has already handed back the urn regained with this summer's 3-0 victory after England slipped to a third successive Test defeat in Australia, losing by 150 runs in Perth.
Former leg-spinner Warne - who criticised Cook's defensive captaincy before the series began - says that England's skipper needs to show that he's in charge.
"I think Cook is a good guy, he's a fantastic spokesman for the team," said the Australian. "The way he conducts himself on and off the field and the way he's got the dressing room together is outstanding, but he really needs to lift tactically.
"He had his best day as a Test match captain in Adelaide and I thought 'here we go, he's improving' and it was great to see because he showed a lot of imagination, he was proactive and he didn't let the game drift.
"But then we got to Perth and I think we all thought 'what are you doing?' I think he went into the mode of 'I've got to bat and I've been under the pump' because he forgot to captain the team. Wherever the ball went he put a fielder and there was no plan or talk about 'this is what we're doing'.
"I just think he needs to grab the team and say 'I'm in charge'. There was too much of Matt Prior moving players, Jimmy Anderson saying 'I want this man over there', Graeme Swann saying 'push him back'.
"Alastair Cook is the captain and he's in charge. He needs to stand up and say 'I'm in charge'. If you look at the Australian team, you know exactly who is in charge - Michael Clarke. There's no-one else waving the field around or bowlers telling players where to go and the 'keeper's not directing traffic.
"Clarke is in charge and Cook needs to take charge now. There shouldn't be wholesale changes. You can stick to the team but maybe shuffle things around. Ian Bell has to bat at number three.
"This is a great opportunity for the senior players who have been wonderful for a long period of time to show why they've been outstanding cricketers for England. They've got two Tests to show how important playing Test match cricket for England is.
"For a young kid to set the example of how to fight in a Test match is a slap in the face for the senior players."
Warne was part of the mighty Australian team that squashed England 5-0 in the 2006/07 Ashes and the legendary spinner says that unless the tourists show more character, they too will suffer a whitewash.
"Australia have had to cop it and it hurt them and they've come back and said 'I've had enough'," he reflected.
"England need to work out how to bowl to a few players and stick to it, they need to show a lot more fight and if they do that in these last two Tests they can get a lot out of it and they can win they can actually win some Test matches.
"If they don't improve their attitude and their fight and Australia are allowed to boss the game and take charge and bully the tail and bowl the way they have, then unfortunately I think it is going to be 5-0."
Former England all-rounder Sir Ian Botham said that the manner of England's defeat offers Cook fresh opportunities.
"If you are going take something from this result and try to look to the future, it gives Alastair Cook a chance to remodel the side so it is his side," he said.
"He inherited a very good side from Strauss but that might give him some incentive and something to look forward to because he's got to find something to get him going because the cricket hasn't helped.
"Maybe that's something for him to think about and maybe Ben Stokes will fit into that future planning."
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