Day two, Wednesday, proved a big one for St Mary's who later faced Pool C winner Mount Albert Grammar School (MAGS) in the opening round of phase two play.
St Mary's led by one goal at the first break, but MAGS won the next three quarters to earn maximum points with a 35-27 win and remain on track for a finals berth.
Manukura won all three of their round robin games to finish at the top Pool B, before taking on the defending champions Saint Kentigern College, who finished second in Pool A, in the second phase of the competition. Saint Kentigern came out on top of an enthralling arm-wrestle 35-34.
Howick College had a dream debut at the national tournament, topping Pool A and going on to beat Waikato Diocesan School for Girls, who finished second in Pool B, 30-26.
Epsom Girls' Grammar School also showed they will be tough to topple with a convincing 52-36 win over St Hilda's Collegiate.
Meanwhile, Palmerston North Girls' High School, Ashburton College, St Paul's Collegiate and St Margaret's College all netted wins in the opening rounds of the bottom 8 pool play.
The remaining top eight and bottom eight round robin games are being played todayto determine which teams will playoff in the finals tomorrow.National selector Kiri Willis said she had seen an "extremely competitive" opening day at the tournament which had set up a challenging second phase as teams were split into the top and bottom eight.
"It's been a pretty high standard from early on. Often we can see teams easing into it on day one but it's been full-on from the start and some very competitive pools.
"The intensity certainly lifts and it's a challenge for the players - both mentally and physically - to bring their best for two games every day. But the girls are pretty primed for this tournament and you can see the excitement. There's certainly plenty of emotion - good emotion - from all teams," Willis said.
New Zealand Secondary School Netball Championship day 1 and 2 (Tuesday and Wednesday) Results
Tuesday:
St Hilda's Collegiate School 39 v Queen Margaret College 27
Mount Albert Grammar School 51 v Ashburton College 25
Epsom Girls' Grammar School 31 v St Mary's Wellington 30
St Andrew's College 27 v St Paul's Collegiate School 46
Howick College 30 v Saint Kentigern College 27
Palmerston North Girls' High School 30 v Christchurch Girls' High School 36
Manukura 30 v Waikato Diocesan School for Girls 26
St Margaret's College 27 v Sacred Heart College 38
St Hilda's Collegiate School 21 v Mount Albert Grammar School 41
Queen Margaret College 34 v Ashburton College 35
St Mary's Wellington 45 v St Andrew's College 20
Epsom Girls' Grammar School 27 v St Paul's Collegiate School 28
Saint Kentigern College 50 v Christchurch Girls' High School 20
Palmerston North Girls' High School 20 v Howick College 35
Manukura 38 v St Margaret's College 22
Waikato Diocesan School for Girls 32 v Sacred Heart College 28
Wednesday:
St Andrew's College 29 v Epsom Girls' Grammar School 53
St Paul's Collegiate School 28 v St Mary's Wellington 32
Ashburton College 27 v St Hilda's Collegiate School 44
Queen Margaret College 25 v Mount Albert Grammar School 56
Manukura 44 v Sacred Heart College 18
Waikato Diocesan School for Girls 40 v St Margaret's College 37
Saint Kentigern College 46 v Palmerston North Girls' High School 20
Howick College 43 v Christchurch Girls' High School 17
St Paul's Collegiate School 44 v Queen Margaret College 19
Ashburton College 33 v St Andrew's College 25
Sacred Heart College 27 v Palmerston North Girls' High School 28
Christchurch Girls' High School 29 v St Margaret's College 36
Epsom Girls' Grammar School 52 v St Hilda's Collegiate School 36
Mount Albert Grammar School 35 v St Mary's Wellington 27
Manukura 34 v Saint Kentigern College 35
Howick College 30 v Waikato Diocesan School for Girls 26