Wellington Phoenix defender Ben Sigmund believes his confidence is slowly returning after being left out of the starting line-up in recent times.

The 29-year old New Zealand international was suspended back in December for an incident against the Melbourne Victory and has only started two games since but after grabbing 15 minutes in the closing stages of the Phoenix's knockout semi-final win over Perth Glory on Sunday, he can feel a bit of confidence creeping back in.

And he believes that is extremely important, especially with an international friendly against Mexico scheduled for next Wednesday and another knockout final next Sunday against the Newcastle Jets.

"When you haven't played for a few weeks the mind starts doubting that you can actually go out and do it," Sigmund admitted.

"It was nice to get that bit of confidence and go on and get a bit of a feel for it and know when my chance comes I can do it.

"I thought with 15 to go they would throw Daniel on for a late winner or something. It turns out Jon McKain got the red card and it turned pretty quickly. It's quite amazing."

Sigmund added that with another knockout final coming up, the Phoenix plan to leave no stone unturned in their quest for the A-League title.

"There are no excuses now it's finals football. As soon as we lose a game of football we're out," he added.