The Juventus and Italy great's arrival on a A$4 million £2.38 million) two-year deal last season helped fire what was hailed as a breakthrough season for the league but the returns for Sydney FC on the pitch were not as sensational.
Del Piero was a class apart but his 14 goals in 24 appearances were not enough to drag the twice champions into the play-offs that decide the league title at the end of the season.
Installed as club captain for this season, 38-year-old Del Piero had looked off the pace in a sometimes physical encounter of the sort Newcastle's marquee signing Emile Heskey might have enjoyed had the former England striker not been injured.
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A crude hack at Del Piero's ankle by former Netherlands defender Kew Jaliens in the 28th minute slowed his pace even further and there were only glimpses of the skill that won him 91 Italy caps.
With nine minutes remaining in the half, though, his team mates finally got him the ball in space and facing goal.
Although he lost possession in the initial challenge, the ball fell kindly for him in the penalty area and, in a blur of backheels and faints, he wriggled through three defenders and lashed the ball past goalkeeper Mark Brighitti.
Sydney's second goal went to Joel Chianese on the hour mark but it was Del Piero's tackle, followed by another surging run towards goal and perfectly weighted pass that allowed the young midfielder the room to finish with a flourish.
The 20,000 crowd was down on the 35,000 who turned up for the corresponding fixture for Del Piero's first start last year but Australia's glamour club will not care too much if the Italian can help them to a third title next May.
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