Substitute Gan put the home side in front on 77 minutes before marquee striker Aloisi added a second on 81 minutes.

The home side had by far the better of the first half but only rarely troubled debutant goalkeeper Reece Crowther, who was playing in place of Mark Paston.

Mark Bridge had two goal attempts in the opening 10 minutes, firstly directing his header into the arms of Crowther.

The next opening was even closer, which had it gone in would have qualified for one of the more bizarre goals of the season.

Crowther pondered far too long on a back pass allowing Bridge to block the clearance with the ball looping from the edge of the penalty area just wide of the goal.

John Aloisi and Kofi Danning had headed attempts on goal but both were unable to made solid contact with Crowther untroubled.

Wellington, with a solid record of two wins from three starts in Sydney, only rarely ventured deep into opposition territory with Paul Ifill's flashed shot across goal their best moment in the opening stanza.

Crowther finally had the opportunity to prove his worth with the 20-year-old making a stunning save from Brendan Gan's header from close-range with a spectacular tip over the crossbar.

Gan had another opportunity from the ensuing corner but this time headed into the ground and wide.

Sydney were edging closer but much like the match against the Central Coast Mariners last weekend, they seemed to lack cutting-edge in the opponent's penalty area.

The visitors opened the second half brightly with Clint Bolton momentarily looking like he might go from hero to villain following his late heroics against the Mariners eight days earlier.

The veteran shotstopper spilling Michael Ferrante curling effort from 25 metres, then scrambling the ball away to safety as onrushing attackers looked to pounce.

Substitute Gan who came on in the first half for the injured Terry McFlynn came closest to breaking the deadlock on the hour mark flashing his shot marginally wide of the post.

Gan it was though that finally had the scoreboard ticking over, powering a header from a Karol Kisel corner into the net in a near-repeat of his first half effort though this time Crowther was powerless to intervene.

The goal from the substitute 13 minutes from time replicating the circumstances of Bridge's winner a fortnight earlier against Adelaide.

This time though it was not to be the only goal of the match with Aloisi doubling the advantage four minutes after Alex Brosque placing an inch-perfect cross following a lightening Sydney counterattack.

The result sets up a mouthwatering top-of-the-table clash next Saturday between Sydney FC and Gold Coast.