It is quite a step up for the 21 year old who is still young in both years and playing experience.
Her rapid elevation is a reflection of the franchise's philosophy. Under coach Janine Southby there has been a focus on bringing younger players through and building towards a tilt at the title.
The team made a late run last year but a poor start cost it a place in the playoffs. Five weeks into this year's tournament and the Steel has dropped three of its four fixtures but those losses have been inflicted in the last three or four minutes of games.
When you are a senior player, as Purvis is these days, it is part of your role to help your team win those critical moments. And that has been what the focus has been on this week as the side prepares for an important match against the Tactics in Christchurch tonight.
''It is a really important game for us,'' Purvis said.
''All three games have been lost in the same way in that last quarter. It is as if when something doesn't go our way we drop our heads a bit.
''I think there is a bit of a lack of experience in our team, so it is about getting a bit of self belief so that is what we are looking at bringing out for the rest of the season because we should be maintaining leads when we've got them.
''Our focus has been on critical moments and finishing off those critical moments. We've set up our go to centre pass and our go to options so we have a back up to go to which will hopefully steady us a bit if things aren't going our way.''
Key players step up during those moments and Purvis certainly feels some of that kind of pressure.
''You do want something to spark the team like a really amazing feed or a really amazing intercept. But I imagine all of the defenders feel the same way and we all try really hard for each other to make that happen.''
Purvis is in her fourth year with the Steel and has 34 games under her belt, so she is still learning her craft. However, there is more expected on her in terms of leadership and she is enjoying that challenge.
''We have put a big emphasis on everyone being responsible for themselves ... but being at the back at goal keep I have a responsibility to talk to the defensive players in front of me just because I can see a lot of the court. Having the confidence of being in the team for a while, I'm not afraid to say a bit more.''
The Tactix have not posted a win this season but when they play well they have great ball speed and athleticism. The Steel will seek to slow its progress and go to its trump card, towering goal shooter Jhaniele Fowler Reid.
It is an even tournament this year and Purvis is well aware of the threat the Tactix pose. That said, the Steel has dominated its neighbour, winning 12 of the 15 matches.
Steel v Tactix
Christchurch, today, 7.40pm
Head to head: Played 15, Steel 12, Tactix 3
Greatest winning margins: Steel 28. Tactix 5
