The England campaign was already battered and bruised after Australia's crushing 3-0 series win with two Tests remaining.
Ahead of the Boxing Day Test at the MCG, opening batsman Warner says veteran spinner Swann pulling up stumps felt like another victory for Australia.
"It's like a little bit of a knockout blow," Warner said.
"It is weird with Trotty (Jonathan Trott) going home and now Swanny retiring.
"For us we look at that and don't know what to think but credit to us we're playing good cricket."
The swashbuckling opener been in sparkling form with two centuries and two half-centuries in three Tests against England this summer.
He says the fact that everyone is contributing is the difference in the side that was winless against England earlier this year.
"That's probably why we're 3-0, because everybody is doing their little bit around the team," Warner said.
"We're going as well as we can."
Australia bowling coach Craig McDermott this week praised his attack as the best in Test cricket and Warner feels the batsmen are in line for the same title.
"We are well on our way," Warner said.
"We've been gelling well together and working hard together in the nets.
"We're playing good cricket."
Warner's the leading runscorer in the series with 457 at 91.40.
"I don't need much for Christmas apart from coming out here and scoring runs for the team and having a Boxing Day victory to go 4-0," he said.
"It's good to be on a high. I've never been on a roll like this before."
Warner made his international debut at the MCG in a T20 against South Africa in January 2009, crunching 89 off 43 balls.
Thursday could be another memorable MCG moment for Warner with a world-record crowd of over 90,800 expected.
"Boxing Day as a kid growing up, you always want to play the Boxing Day Test, but an Ashes Boxing Day Test really ticks the boxes off," Warner said.
"You have to pinch yourself, really, because you don't get to play in front of 90,000 people every day of your life so coming out here on Boxing Day will be a very special moment."