Sydney FC kept themselves in A-League finals contention with a sensational 2-0 upset win over the Central Coast Mariners on Saturday.
Sebastian Ryall put the hosts in front in the opening half and Joel Chianese doubled the advantage after the break to lift the Sky Blues into fifth spot with their sixth win in a row at Allianz Stadium.
The Mariners, suffering back-to-back losses for the first time this season, remain in second spot but Sydney FC did cross-city rivals and ladder leaders Western Sydney Wanderers a big favour.
They can widen the gap at the top to five points with a win over bottom-placed Wellington on Sunday.
The win gives Sydney a crucial boost ahead of a difficult run home as they face third-placed Melbourne Victory next week and the Wanderers the week after before travelling to Brisbane for their final-round clash.
The Sky Blues came out swinging, creating a flurry of chances in the first 12 minutes with Joel Griffiths, Brett Emerton and defenders Terry McFlynn and Tiago Calvano all attempting strikes.
It was defender Ryall who put the hosts in front in the 26th minute, getting on the end of a superb McFlynn cross to score his third of the season.
The Mariners looked likely to respond soon after the restart as the season's top scorer Daniel McBreen missed an opportunity to level.
Michael McGlinchey forced Sydney gloveman Vedran Janjetovic into action moments later with a shot of his own.
McBreen threatened again 10 minutes into the second half, curling a dangerous strike just past the post.
Compelled to change things up, Mariners coach Graham Arnold used his full quota of substitutions in the second half, bringing on Mitchell Duke, Oliver Bozanic and Zachary Anderson for Mile Sterjovski, Nick Montgomery and Pedj Bojic in an effort to add some more pace up front.
Italian superstar Alessandro Del Piero had the 16,155 crowd at Allianz Stadium on their feet when he let rip with a strike which forced a diving save from Mariners 'keeper Mathew Ryan.
Sydney coach Frank Farina made a change of his own, bringing on Chianese for Griffiths in the 69th minute and it proved a masterstroke as the young gun widened the gap less than five minutes later with a 73rd minute goal.
McBreen had a perfect chance to get one back with two minutes to go but sent it over the crossbar.