A late goal from Sydney FC marksman Sasho Petrovski has dealt Adelaide United its first-ever A-League loss, 2-1, after a controversial finish to Sunday night's top-of-the-table clash at Aussie Stadium.

Petrovski ended Adelaide's unbeaten run in the 88th minute when he jabbed home Sydney's second goal to break the deadlock.

Two minutes later, Adelaide's appeals for a handball by Sydney defender Jacob Timpano in a goalmouth scramble also involving Reds striker Shengqing Qu was denied by referee Mark Shield.

The Reds believed the ball had crossed the line but were denied by the official.

It followed a sometime fiery second-half between the two best teams in the competition.

After a predominantly dour first half, Adelaide broke the deadlock six minutes into the second term.

Defender Michael Valkanis, left unchecked in the box, beat Sydney defender Alvin Ceccolli in the air to head home Shengqing Qu's corner kick.

Sydney's David Carney then levelled the scores just three minutes later. Adelaide keeper Daniel Beltrame fumbled a thumping 25-metre volley from Terry McFlynn, allowing Carney to scoot into the goalmouth and ram the ball into the back of the net.

Sydney had the better of the chances in the final 30 minutes, and finally scored when Adelaide failed to clear a Steve Corica free kick, which drifted to a waiting Petrovski at the far post.

The win, Sydney's first at home after a draw and loss, moved the competition favourites to within a point of leaders Adelaide after the first full round of the competition.

Brought to you by AAP © 2024 AAP