The burly Symonds, who was voted Australia's one-day player of the year last week, held the innings together after the hosts slumped to 52 for three at one stage.
He found a willing ally in Damien Martyn as the pair raised 137-run stand for the fourth wicket to provide the much-needed stability to the innings before they endured another late-order collapse losing their last five wickets for 24 runs.
Symond struck 91 off 101 balls, laced with seven boundaries while Martyn chipped in with a fine half-century and just when it looked that the duo would bat through the entire fifty overs, Afridi struck.
Afridi first had induced Martyn to sept down the pitch to a ball that spun sharply and had the Australian No. 4 neatly stumped by Kamran Akhmal in the 41st over. Darren Lehmann was out next ball with the total at 190 for five, caught behind attempting a reverse sweep.
Simon Katich blocked the hat-trick ball from Afridi and also survived a confident shout for caught behind on the first ball of the 46th over after appearing to glove a ball down leg side off Razzaq.
But he failed to make capital of that perishing, offering a leading edge to substitute Yasir Hameed off Razzaq two balls later as Australia slipped to 213 for six.
Razzaq removed well-entrenched Symonds with the Australian allrounder swiping at a short ball and directing a catch to Inzamam-ul-Haq in the covers.
Shane Watson was taken by Mohammad Hafeez off Razzaq for 4. Brett Lee made 13 before being castled by Naved-ul-Hasan with the Australian total reading 235 for nine.
Last-man Glenn McGrath was run out when he dashed off for a sharp single but failed to beat wicketkeeper Kamran Akmal's shy at the stumps as the Aussies folded up for 237.
Earlier, Australia made a poor start when Michael Clarke, promoted to open the innings at the expense of out of form Matthew Hayden was adjudged lbw to Naved-ul-Hasan for nine with the total at 29.
Adam Gilchrist scored a breezy 24 before he drove uppishly to mid-off, where Razzaq took a left-handed catch out of the air with the total at 51. Skipper Ricky Ponting was bowled by Rao Iftikhar Anjum for 11 in the next over.
Abdul Razzaq was the most successful Pakistanb bowler returning with figures of 3-33 off 10 overs. Leggie Shahid Afridi and fast bowler Rana Naved-ul-Hasan claimed two wickets apiece.