Parish continued to threaten and within five minutes of the restart, she found her second goal.
Cambridge responded with Te Puke centre-back Talia Hope anticipating to clear the ball a metre before the line.
Just past the hour mark, Cambridge got their first, despite calls for off-side, and then drew level with 10 minutes to go, scoring from a corner. Calls for hand ball went unheard and the game was set for 30 minutes of extra time.
The sides still couldn't be separated, bringing the penalty shoot-out into play.
Sarah Earle stepped up to bury the first penalty, while Mettenleiter saved Cambridge's first.
With Cambridge missing two and another Mettenleiter saves, the keeper was given the chance to win the game which she did, winning herself the Anann player of the day accolade.
In the other semifinal, Cambridge's second team beat Thames 6-5. The final will be at Korikori Park in Hamilton at 10am on Sunday.