But, despite stumbling in to the playoffs, Ngata thought Wellington would be too strong for Sydney, a side they have beaten three times already this season with 2-1 and 4-2 wins at home and a 1-0 road victory.
"I think Sydney's going to have to play them off the park to win. They've got the third-best defence in the league, the Phoenix. I think [Ben] Sigmund and [Andrew] Durante at the back, you can't fault them. They got run a little bit ragged against Melbourne Heart I thought a couple of weeks ago in Melbourne.
"But, Manny Muscat on the right, Tony Lochhead on the left, all four of them are really solid players and Sydney are going to have to come down here and play through them. I find that very difficult to see how they're going to penetrate through the middle, particularly with Sigmund and Durante there."
Hay, who played for Leeds United in the English Premier League before captaining the now-defunct New Zealand Knights in the A-League during the 2006-2007 season, said the Phoenix had the big names to do the job.
"Particularly the fact that they're playing at home," Hay said. "Of course, they've got to be heavy favourites. They're heavy favourites in my eyes and I think with the bookies as well. Despite the fact that they had those two losses on the bounce, they've proved three times this year against Sydney that they're the better side.
"I think they've probably just got a little too much experience at this time of year as well. Your Paul Ifills, your Andrew Durantes, Tim Browns, those guys know what it takes to win crucial football games. I look at that Sydney side, they're probably going through what they'd call a rebuilding stage. They're young and light in terms of that hard-nosed experience.
"So that's why I think the Phoenix will probably do it."
Brown, a foundation member of the club, announced his retirement from football this week and the side will want to send the veteran midfielder out on a high note.
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