Detective Sergeant Tim Smith said police investigations established that 9000 text messages were sent between the pair over an eight week period - during the day and night.
"It just had such an emotional impact on the victim with her schooling and her self-esteem."
The charge of ill treatment of a child relates to the emotional and psychological harm the young girl was subjected to through her relationship with Carlisle, Mr Smith said. The charge of attempting to pervert the course of justice relates to Carlisle putting pressure on the young girl to lie to police about their relationship, deleting texts and emails and changing phones so they could continue communicating after being told to stop their relationship.
Mr Smith said this was a clear example of how young, vulnerable people could be manipulated by an older adult who in this case, successfully groomed the girl into an emotional but harmful relationship.
"This woman [Carlisle] was a volleyball coach. She was in a position of power and trust and unfortunately the victim was coerced into a damaging psychological partnership where self-harming and suicide was encouraged.
"The girl was a normal, happy teenager before meeting Carlisle but she ended up relying heavily on her coach as her self-esteem plummeted," Mr Smith said.
Police say the investigation was unique in that it involved a female sports coach who had developed an intense emotional relationship with a young girl.
"If this had been a male coach, there would have been instant red flags that parents, teachers and fellow coaches would have reported."
Mr Smith said the school involved would have had no reason to be suspicious of Carlisle. But it was incumbent on all schools and sports clubs to keep a watching brief over all coaches or other adults involved in school or club activities.
"While in this case the school had no reason to question Carlisle, it does raise the issue of the need for extra vigilance around the relationships coaches and other adults can form with students.
"We are just pleased that the victim now has a happy, normal life and is able to move on from these damaging experiences."
The girl's name and the school she attended are suppressed.
Carlisle, a married mother-of-three who is now aged 29, became fulltime regional manager for Volleyball Hawke's Bay in April 2012.
Judge Jonathan Down told the court: "This is an extraordinary case. It is utterly unique.''
While the relationship extended to physical touching, in which Carlisle cradled the girl's head in her arms and slept with her in the same bed, the judge accepted there was no evidence of sexual motivation.
In statements available to the court, the girl spoke of the deterioration in her life as the relationship developed, and as Carlisle tried to have her believe her life was miserable and her family were against her and did not love her.
Carlisle also undermined the efforts of a psychologist to help the girl, despite having been warned by the psychologist and the girl's parents, after it was discovered the girl had self-harmed.
The judge accepted a submission from Crown prosecutor Steve Manning that it was not so unique that the sentencing should not include an element to deter others.
Mr Manning noted there had been another case in court elsewhere in the country in recent weeks involving a coach's inappropriate relationship with a pupil.
Volleyball New Zealand CEO Paul Cameron said the organisation supported the sentence handed down to Carlisle.
The behaviour of Carlisle, whose employment ended soon after details of the relationship emerged, was ``totally unacceptable and will not be tolerated''.
The organisation is currently drafting a Child Protection Policy which Mr Cameron said all codes should be working-on to prevent such situations occurring.
