"The New Zealand standards are very hard," she conceded as she looked forward to the next month. "But, it is what it is."
Running in the Hawke's Bay-Gisborne centre colours on Saturday, it was never going to be easy against three-time defending champion Canterbury runner Katherine Camp, and Auckland hope Jennie Hauke, who she had to mow down after both set personal bests at an Auckland clubs meet on February 23.
On Saturday Manning took control at the bell quickly kicking clear of the field, ultimately beating runner-up Camp by almost two seconds.
It was a surprise, having gone through a slow first 400m in a little under 64s, when she said she thought: "This isn't going to be what I'm trying to do. I've got to go."
Seeing the track clock at 2m 3sec was a surreal moment -- she thought it was more likely to have been anything up to two seconds slower.
One of six Hawke's Bay-Gisborne Centre gold medallists in the four days of Senior, Under 20 and Under 18 championships at Mitre 10 Park, former Napier Girls' High School pupil Manning was also runner-up on Sunday to former Taradale High School pupil Laura Nagel in the 1500m.
Nagel, now 30 and based in North Harbour, turned in a starring act, adding the Senior Women's 1500m and 5000m double to her one mile and 3000m titles won earlier in the season.
In the 1500m, she took control from the outset, setting the pace, ramping it up over the last two laps and kicking clear to win 4m 16.68s, the second-fastest time of her career.
Manning finished strongly to claim the silver medal with a time of 4m 20.05s, to pip Camp, also a former national champion at the distance as she ran 4m 20.82s.
The runner-up in the 5000 metres was former Woodford House pupil Eva Goodisson.
Nagel told Athletics NZ media: "I've been saying for a while that I'm not a 1500m runner, but I hoped to perform well which I think I did, I'm really stoked.
On completing the bag of four titles, she said: "It couldn't get much better, I have really enjoyed the season and to win the 1500m title as well has been awesome. The quality of women's running has been amazing, and I've enjoyed the camaraderie."
The other HBG Senior winner was Georgia Hulls, with a 23.1s 200m, beating runner-up and Canterbury rival Rosie Elliott by 0.31s.
Havelock North High School pupil Karsen Vesty emerged as another prospect in a growing list of promising male middle-distance runners when he won the Men's Under 20 1500m.
Ryan Shotter won the Men's Under 18 100m and anchored an all-Napier Boys' High School Hawke's Bay-Gisborne team to win the age group's 4x100m relay. Lorcan Rabbitte, from Havelock North High School, won the Men's Under 18 2000m steeplechase.
The match-up of Olympic Games throwers Tom Walsh and Jacko Gill in the shot put faded a little when Gill sat out the last throws with an injury. They still finished first and second respectively, with home-venue thrower Nick Palmer delivering a personal best of 19.06m to claim third place.
Among other highlights of the second national athletics championships in Hastings in a row was the 11.07s winning women's 100 metres time of Taranaki sprinter Zoe Hobbs, the fastest ever run by a New Zealand woman. She'd run an 11.15s national record on the same track on February 12, but the latest effort could not be recognised as the new mark because of excessive wind assistance.
Former Hastings sprinter Briar Toop's 32-year-old record would also have been broken but for the wind, when 15-year-old Auckland sprinter Talia van Rooyen won the Women's Under 18 final in 11.5sec.
Canterbury 100m sprinter Tiaan Whelpton, who would have broken the NZ senior men's record on the track end in January but for the wind, was deprived another chance when a mid-race hamstring injury ruined the big match-up with Eddie Osei-Nketia, who had come home from Australia to run 10.2sec to claim the title for the third time.
There were two New Zealand records with Portia Bing winning the women's 400m hurdles in 55.44s, shaving 0.6s from the mark she set 13 days earlier, and Tori Peeters threw the javelin 62.4m, 36cm further than the record she set two years ago.
Meanwhile, US-based Hawke's Bay runner Geordie Beamish has been confirmed as one of six athletes to represent New Zealand at the World Indoor Championships in Belgrade, Serbia, on March 28-20.
Beamish, 25, will run the 3000m, having smashed the New Zealand indoor record for the distance with a 7m 39.5s stunner at the Milllrose Games at The Armory in New York last month, clipping more than four-and-a-half seconds off the previous record (7m 44.16s) set by Olympic Games representative Zane Robertson in 2014. Beamish's best outdoors is 7m 42.39s in Italy last August.
Results of events with Hawke's Bay-Gisborne athletes in the medals were:
Senior:
Men Shot Put: Tom Walsh (Canterbury) 21.55m, 1; Jacko Gill (Auckland) 21.21m, 2; Nick Palmer (Hawke's Bay Gisborne) 19.04m, 3.
Women 200 Metre: Georgia Hulls (Hawke's Bay Gisborne) 23.1s, 1; Rosie Elliott (Canterbury) 23.41s, 2; Isabel Neal (Auckland) 23.66s, 3.
Women 800 Metre: Holly Manning (Hawke's Bay Gisborne) 2m03.76s, 1; Katherine Camp (Canterbury) 2m05.68s, 2; Jennifer Hauke (Auckland) 2m05.95s, 3.
Women 1500 Metre: Laura Nagel (North Harbour) 4m16.68s, 1; Holly Manning (Hawke's Bay Gisborne) 4m20.05s, 2; Katherine Camp (Canterbury) 4m20.82s, 3.
Women 5000 Metre: Laura Nagel (North Harbour) 16m33.77s, 1; Eva Goodisson (Hawke's Bay Gisborne) 16m39.12s, 2; Brigid Dennehy (North Harbour) 16m39.73, 3.
Under 20:
Men 800 Metre: Zane Powell (Auckland) 1m 55.58s, 1; Karsen Vesty (Hawke's Bay Gisborne) 1m 56.23s, 2; Luke Hitchcock (Auckland) 1m 56.79s.
Men 1500 Metre: Karsen Vesty (Hawke's Bay Gisborne 3m54.81s, 1; Zane Powell (Auckland) 3m55.09s, 2; Charlie Hazlett (Canterbury) 3m57.44s, 3.
Men 4x400 Metre Relay: Auckland 'A' 3m19.83s, 1; Hawke's Bay Gisborne 'A' (Charles Roil, Karsen Vesty, Callum O'Keeffe, Kairon Pimm) 3m22.58s, 2; Manawatu Wanganui 'A' 3m23.22s, 3.
Men Shot Put: Liam Ngchok-Wulf (Auckland) 17.81m, 1; Trent Hogg (Southland) 15.17m, 2; Cooper McDougall (Hawke's Bay Gisborne) 14.95m, 3.
Men Hammer Throw: Liam Ngchok-Wulf (Auckland) 57.23m, 1; Max Abbot (Wellington) 51.38m, 2; Hanno Nel (Hawke's Bay Gisborne) 49.15m, 3.
Under 18:
Men 100 Metre: Ryan Shotter (Hawke's Bay Gisborne) 10.95s, 1; Ben Lambert (Wellington) 10.98s, 2; Asher Pettengell-Brand (Canterbury) 11s, 3.
Men 200 Metre: Asher Pettengell-Brand (Canterbury) 22.33s, 1; Rylan Noome (Hawke's Bay Gisborne) 22.37s, 2; Ben Ward (Auckland) 22.66s, 3.
Men 800 Metre: James Ford (Auckland) 1m55.3s, 1; Liam O'Donnell (Canterbury) 1m55.82s, 2; Callum O'Keeffe (Hawke's Bay Gisborne) 1m56.14s, 3.
Men 2000 Metre Steeplechase: Lorcan Rabbitte (Hawke's Bay Gisborne) 6m08.89s, 1; Louie Endres (Waikato BoP) 6m11.48s, 2; James Mcleay (Southland) 6m17.47s, 3.
Men 4x100 Metre Relay: Hawke's Bay Gisborne 'A' (Liam Kilby, Rylan Noome, Logan Woods, Ryan Shotter) 43.26s, 1; Canterbury 'A' 43.55s, 2; Auckland 'A' 44s, 3.
Men 4x400 Metre Relay: Canterbury 'A' 3m26.66s, 1; Auckland 'A' 3m32.19s, 2; Hawkes' Bay Gisborne 'A' (Jackson McKay, Camden Russell, Tayne Patel, Lorcan Rabbitte) 3m39.78s, 3.
Women Javelin Throw: Mia Bartlett (Wellington) 37.08m, 1; Vaya Chaplow (Hawke's Bay Gisborne) 36.23m, 2; Karmen-Elizabeth Maritz (Auckland) 35.39m, 3.
Women Pole Vault: Maya Grundy (Auckland) 2.96m, 1; Lilli Bing (Auckland) 2.96m, 2; Angalla Carney (Hawke's Bay Gisborne) 2.96m, 3.