Wellington will host a HRV Cup Twenty20 semi-final on Friday.
They shut out Northern Districts in their virtual quarter-final at the Basin Reserve.
After scoring 181/1, the home side restricted the Knights to 172 to take a nine-run win.
Captain Michael Papps says their composure bodes well.
"It was really good that we were able to go out and hold our nerve in a tight situation towards the end there and get over the line. It's important going into the finals series that you have that ability to win the tight ones and we put that out there.''
Their semi-final opponents will be either Northern Districts or Auckland, who remain alive after beating Canterbury.
Leaders Otago will host the final after beating Central Districts by three wickets in New Plymouth.