Sigmund made a comeback as a substitute at right-back for the frantic final stages of last weekend's 3-2 loss to Newcastle Jets and is in the squad for Friday night's game against Melbourne City at Westpac Stadium.
"I know I'm not starting the game, but I'm hoping to get on at some stage and contribute to the team," Sigmund said.
"Ernie (Merrick, the Phoenix coach) is grooming the young fellow, Dylan Fox, for the future in the central defence. I'm ready to go if he wants to use me.
"I just want to finish on a high and finish with my mates the way I've played my whole career, giving it 120 per cent in every single game and every training session and making sure I keep my standards and the club's values up every week.
"I just want to be remembered as a guy who never gave up, to be honest."
When Sigmund collapsed during Wellington's 2-1 loss to Western Sydney Wanderers at Pirtek Stadium in November, many assumed it was a delayed reaction to a head knock he had sustained earlier in the match.
But Sigmund said he had been battling ill-health for a month going into the game and that the problem was only diagnosed afterwards.
"I found out I had Giardia, which is a bug you can get from water," he said. "I'd been playing with it for a month and against the Wanderers I just passed out. I think I was completely exhausted and my body had nothing left to give.
"You get diarrhoea as part of it and I'd lost 5kg. I felt awful, but I kept playing with it, just battled through, but then it caught up with me. It turned out my daughter, Ashley, had it first and I must have caught it off her.
"We both battled along thinking it was just a stomach bug, but I ended up feeling so awful I had some tests done and they said I had Giardia and I had to get to the hospital and get medication and start treating it.
"You've got to take a course of heavy antibiotics to kill the bug and you can still feel like rubbish for two or three months or even up to six months after that, because your body takes a long time to get over it and readjust. It was around eight-to-10 weeks for me.
"My daughter and I are fine now. I've been desperate to get back playing and I've worked really hard. It's my last year and I wanted to be fully committed right to the end and get back on the field, which I've done now. I want to play as much as I can over the last seven rounds."
Sigmund, 35, is known as a hard-man but he believes he'll still get emotional when it finally comes time to play his last game.
"It will hit me at the death, I think," he said.
"I know my body is ready to stop. I've had two operations on my hip and it's feeling sorer every week and I feel like I know it's the end and I've given it a good crack and I'm pretty happy with how my career has gone and what I've achieved.
"I've got no regrets. I just want to enjoy getting to the end of my career and 35 is not a bad innings, to be honest.
"I'm mentally tired as well as physically tired, but I've worked very hard to get back for the last few rounds and I really want to make them count."
Sigmund has already taken important steps towards his post-playing career, having set up a business - Fully Committed People Development - designed to help footballers as well as people in other sports and the corporate sector.
"I've created the business around what I didn't have when I was younger and what I missed out on and what I probably needed," he said. "It's about providing the support people need to be as good as they can be in their chosen field."
Sigmund, who was a long-time New Zealand All Whites representative as well until his retirement from international football in 2014, said he was also detailing his life story for a book.
"I'm writing an autobiography that will be out in May, at the end of the season," he said. "I'm really enjoying the experience of putting that together."
For Melbourne City, long-term absentees James Brown and Marc Marino are surprise inclusions to the squad while Anthony Caceres returns after serving his second suspension in just three matches since his switch from Central Coast Mariners.
Brown, 26, hasn't played an A-League match for 11 months after suffering a foot injury while Marino, 19, returns to contention for the first time since last May's finals series.
The pair are unlikely starters in New Zealand after replacing Wade Dekker and Steve Kuzmanovski for the trip across the Tasman, where City will go top of the A-League by defeating the Phoenix.