Western United mounted a comeback from 3-0 down but couldn't overcome a 10-man Melbourne City, who prevailed 3-2 in their A-League clash at AAMI Park.
Melbourne City have bolstered their hold on second place in the A-League, with Jamie Maclaren scoring a brace to beat Western United 3-2 in front of 8,577 fans at AAMI Park.
The hosts led 3-0 at halftime before two United penalties - scored by Besart Berisha and Alessandro Diamanti - got the visitors back in the game.
But City held on, with coach Erick Mombaerts left relieved after late lapses almost completely undermined his side's "perfect" first half.
"Maybe our players want to test me - if I'm in good health for the new year - maybe it's a good test," Mombaerts said.
The win extended the gap between City and third-placed Perth Glory to four points, with Western United a further point behind.
United and City made five and six changes respectively to their starting line-ups, and it was the home side's adjustments which paid dividends early.
Lachlan Wales drove into the box and his cross was bundled over the line by Socceroos striker Maclaren just five minutes in.
In the 36th-minute, Craig Noone dinked the ball over the United defensive line, with Adrian Luna sneaking through and slamming home a volley.
A calamity of United errors helped City to their third goal.
Luna thumped a long ball forward, United defender Andrew Durante and goalkeeper Kurto collided, and Maclaren took possession and guided home into an open net his 12th of the campaign just before halftime.
United worked their way back into the game in the second half.
Josh Cavallo was brought down by keeper Dean Bouzanis and Berisha slotted home his spot-kick with 15 minutes remaining.
Minutes later, Harrison Delbridge conceded a second penalty when he slid in to tackle Dylan Pierias, and the ball hit his arm.
After a VAR review, Delbridge was ruled to have denied a clear goal scoring opportunity and had his yellow card upgraded to red.
Diamanti powered home to make it 3-2 but City held on for all three points.
"I thought they were a lot more intense than what we were in that first half - we could have been and should have been better with the ball as well," United coach Mark Rudan said.
"But in the second half it seemed to change - we blooded some more youngsters and I think the big story for our football club is the amount of young players that got their opportunity today."
Given the smoke haze over Melbourne's CBD throughout the day, the air quality was monitored throughout the lead-up to the contest and during the game, with club doctors consulted and the game going ahead.
Mombaerts said he didn't think his players were affected by the conditions, but Rudan described the conditions as "testing" and said he "thought the game should have been called off".
"Some of the players came back into the dressing room and spoke about how difficult it was to breathe - they were really feeling it down their throat and their lungs," he said.
"But we've got some smarter people than me - I'm not a doctor by any stretch of the imagination - so they know what's safe and not safe."