The 27-year-old, who scored his first A-League goal to hand the Phoenix a 1-0 win over Newcastle Jets on Friday night, admitted it had been a tough decision to stay, particularly as wife, Rebecca, is expecting the couple's first child at the end of the month.

"My family are there and I have business commitments as well, so it was a tough decision, but in the end I thought 'if you are enjoying your football as I am, why go elsewhere?'," he said.

"The fact that Dura (captain Andrew Durante) and Iffie (Paul Ifill) have just re-signed was a factor in my decision as was (coach) Ricki (Herbert) staying with the club.

"Ricki is the only coach I've had in my professional career and he has had a major influence on me.

"He knows what people are all about and gets the best out of you."

Muscat, who joined the Phoenix from Victorian Premier League team Green Gully in 2008, has been a vital part of the A-League club's success during his four years in Wellington.

His versatility has seen him play at both right and left-back as well as in the midfield.

"With the new contract and a new baby I'm starting a new journey and am looking forward to it," the Maltese international said.

"The only change I'd like to see is me return to the defensive midfield role I prefer. I've been happy to fill in at right-back but hope to convince Ricki I should be in midfield where I feel more involved in the game."

His signing means Herbert now has 10 players contracted for next year with Muscat joining Durante, Ifill, Ben Sigmund, Tony Lochhead, Tim Brown, Leo Bertos, Lucas Pantelis, Jimmy Downey and Mirjan Pavlovic on the playing roster beyond 2011-12.

Those off contract at the end of the season are Daniel, Mark Paston, Tony Warner, Brent Griffiths, Vince Lia, Niko Tsattalios, Alex Smith, Nicky Ward, Dani Sanchez, Chris Greenacre and Cameron Lindsay.

Muscat's winner on Friday night earned the Phoenix back-to-back away wins for the first time in their history and saw them move above Melbourne Heart into third spot on the ladder.

They play the Heart in the New Zealand capital on January 29.