Spectators arriving at the ground early in the morning were hit by a monsoon-like deluge and it was soon clear that despite the improving weather play would not start on time.
Despite continued media speculation, Flintoff denied there was a rift in the England camp and said the mood was upbeat ahead of the Sydney match.
Finally, the toss took place at 11.10am local time (0010 GMT) and an 80-minute session ensued.
"The side are up for this last Test. We feel we have a point to prove," he added.
Strauss immediately looked anxious to score quickly but had difficulty locating the middle of his bat.
Sydney traditionally favours spin and England are considering a twin-spin attack with off-spinner Jamie Dalrymple joining Monty Panesar with fast bowler Sajid Mahmood possibly making way.
His first boundary was an edge of Lee that flew only marginally wide of the slip cordon and his second also came off the edge of the bat.
It will be Langer, Warne and McGrath's final Test for Australia
Strauss' best shot came one ball after he was dropped - an authentic on-drive off McGrath.
But Australia are confident in their solitary spin wizard Shane Warne, who after 144 Tests and 706 wickets is calling it a day.
But it was no real surprise when he was out soon afterwards - attempting a cut shot at a ball that hurried onto him.
It will be his last Test hurrah, along with veteran seam bowler Glenn McGrath and opening batsman Justin Langer as the golden generation retires.
Adam Gilchrist had few problems taking the catch and Lee's first ball at Ian Bell was a short-pitched snorter that the right-hander did well to defend safely.
And it will also be the last Test match in charge for Australia coach John Buchanan, who will quit after the World Cup, after eight years at the helm.
Bell clipped Stuart Clark to the fence at square leg for his first boundary while Cook, who had been watchful, began to grow in confidence.
Australia are set to name an unchanged side as Ricky Ponting aims to become the first captain since Warwick Armstrong 86 years ago to beat England 5-0.
Warne said: "We're all enjoying it as much as we can - it's not about Warne and McGrath, it's about the side - a whitewash is what we want."
Ponting said Australia need to remain focused if they want to achieve the rare feat of a clean-sweep.
"As long as we all keep our emotions in check, then hopefully the performances that we've been putting on the board can continue," he said.
He also praised Buchanan for helping to main Australia's number one position in Test and one-day cricket.
"He's been coaching a very talented team. What you've seen some of the players do has been a lot of the time pretty extraordinary, so he's got to take a lot of the credit for that," Ponting added.
SCG head curator Tom Parker said the Test wicket had a good covering of grass and moisture.
"I've been monitoring the moisture in this pitch, just keeping it topped up to keep the seal in the pitch," Parker said Monday.
On day three you'll start to see the turn come into the game SCG head curator Tom Parker
"I think it will be fine. There will be no more moisture than you would normally see in the pitch.
"The ball will probably move around for the first session and a half, especially if we get the cloudy conditions here at the SCG.
"You've seen that when it's cloudy, the ball seems to swing through the air a bit and then it should settle down and by day two it'll be a good batting pitch and then on day three you'll start to see the turn come into the game."
The start of the match could be held up as showers are forecast in Sydney but there is set to be fine weather for the rest of the Test.
Teams: Australia (from): Ricky Ponting (captain), Justin Langer, Matthew Hayden, Mike Hussey, Michael Clarke, Andrew Symonds, Adam Gilchrist, Shane Warne, Brett Lee, Stuart Clark, Glenn McGrath, Mitchell Johnson.
England (from): Andrew Flintoff (captain), Andrew Strauss, Alastair Cook, Ian Bell, Kevin Pietersen, Paul Collingwood, Chris Read, Jamie Dalrymple, Sajid Mahmood, Steve Harmison, Matthew Hoggard, Monty Panesar.
