Sydney FC players celebrate the goal of Jacques Faty during their 3-0 win over the Wellington Phoenix at Westpac Stadium in the capital.

Wellington Phoenix's four-game winning streak came screeching to a halt in a 3-0 loss to Sydney FC at Westpac Stadium on Sunday.

The A-League leaders were missing seven players to international duty and the Sky Blues capitalised to join Melbourne Victory and Perth Glory on 41 points - one behind the Phoenix.

The contest was all but over by halftime as Sydney took a 3-0 lead into the sheds.

They hadn't played the Phoenix off the park but things fell their way and they were good enough to put the ball in the back of the net.

Jacques Faty kicked things off in the ninth minute after the Phoenix failed to clear from a corner and a goalmouth scramble ensued - Sydney's centre back beating goalkeeper Glen Moss at his near post with his left boot.

The evergreen Shane Smeltz - starting in place of golden boot leader Marc Janko (Austria) - then doubled the advantage in the 28th minute.

There were howls of disgust from a small 6236 crowd impacted by the Cricket World Cup final but replays proved linesman Glen Lochrie made the correct decision to keep his flag down.

Christopher Naumoff had had a speculative strike from distance and it fell fortuitously at the feet of the veteran New Zealand striker.

At first glance it appeared Smeltz was well offside but makeshift right back Matt Ridenton was caught out of position and had played him onside as the goal poacher made no mistake.

Graham Arnold's men then grabbed a third scrappy goal in the 40th minute.

Again, the Phoenix failed to clear from a corner, Bernie Ibini had a hit, Sebastian Ryall got a touch and it was credited as a deflected Manny Muscat own goal.

"We were outplayed, the better team won but I don't feel as though the goals were anything special," said Phoenix coach Ernie Merrick.

"It was really sloppy marking from two corner kicks and in the penalty box, the ball fell to a striker who appeared offside - I don't think he was offside, I think young Matty was playing him on. We really couldn't get our midfield going. I don't have concerns. We've been playing great football and we're still top of the league. You put it in perspective and say that's a real learning experience. It's better having it now than in the finals."

There was drama midway through the second half, with Albert Riera and Smeltz both sent off in the space of two minutes.

Riera was dismissed by referee Peter Green for a second yellow card as the frustrated midfielder made a clumsy challenge on Milos Dimitrijevic.

Smeltz was then shown a straight red for kicking out at his former team-mate Ben Sigmund.

The Phoenix host the Victory - who have a game in hand - at Westpac Stadium next Sunday in another game of vital importance as the race for the Premier's Plate heats up.

"Riera's out next week and Vince Lia looks like he's got a minor tear of his hamstring so we'll have to see how he comes up," Merrick said.

"I think [Victory] are [the benchmark team]. Player for player I think they're the better team."

Sydney coach Arnold revealed afterwards that the Phoenix had provided him with some extra coaching ammunition.

"Your matchday magazine was very nice to us and I used that for motivation at halftime," Arnold said.

"In that article it was written that our defence was pretty poor so we used that to motivate the team at halftime when we were up 3-0."

AT A GLANCE

Sydney FC 3 (Jacques Faty, Shane Smeltz, own goal) Wellington Phoenix 0. HT: 3-0 Crowd: 6236