The outspoken 36-year-old said at the start of 2005 that Australia would roll their old foes 5-0 in the Ashes series in England only to see his forecast ridiculed as Michael Vaughan's side battled to an impressive 2-1 series victory.
"I think it will be 5-0 this time," McGrath told reporters after the team touched down in India for their Champions Trophy campaign. "I am never going to predict that Australia will lose a Test. England is not the same team as it was and I am disappointed in them.
"To say anything else would be negative. If we're going to win 2-1, or 3-2, which games are we going to lose?"
McGrath has not played a Test since January and made his tentative international return for Australia in the tri-nations series in Malaysia last month.
McGrath, who has taken 542 Test scalps in 119 matches, said injuries had not helped England but pinpointed the loss of captain Vaughan as one of the main reasons why he fancied Australia's chances of regaining the urn.
"Obviously with the captain changing it does unsettle the team a bit. The fact that Vaughanie did such a great job and had the same team to work with made it a lot easier," he was quoted as saying in the Australian newspaper.
"With Freddie (Andrew Flintoff) now being captain it's a huge ask because he is such a pivotal guy in both their batting and bowling line-ups. He's a class player and seems mentally strong."
The five Test Ashes series starts in Brisbane on November 23.
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