Nearly 50 per cent of lesbians had been personally targeted, three-quarters had heard hurtful verbal slurs, and most players in youth sport remained either fully or partially in the closet.
For Ms Sills, who had been playing soccer for a decade before she came out, team-mates have been welcoming. But as her study will explore, being "accepted" wasn't everything, as seemingly harmless things could bring hurt.
Simple changing room chatter among team-mates, for example, could exclude or marginalise an LGBT player, as could being unintentionally treated differently by a coach.
"Sometimes, with certain groups of people, especially if they are new, and they find out a teammate or a coach is queer, they don't trust or know what to expect from them until they get to know them."
Associate Professor Virginia Braun, who will oversee the study, said: "There is a real need to understand what's going on, and the impact it has on players."
Even subtle discrimination could keep gay players in the closet or discourage them from sport altogether.
Labour's associate sport and recreation spokeswoman, Louisa Wall, was aware of a number of cases where players had been treated differently because they were lesbian.
"Obviously that treatment has resulted in a reluctance for players to come out and be who they are."
A spokesman for Sport New Zealand said discrimination had no place in sport and any new research was important.
LGBT on our fields
45% have been personally targeted.
76% have heard verbal slurs.
9% have been bullied.
4% have been verbally threatened.
2% have been physically assaulted.
76% are completely or partially in the closet while playing youth sport and many fear discrimination.
Source: Out on the Fields study (2015)
Those interested in taking part in the study (participants must live in Auckland) can contact Sophie Sills via email at ssil028@aucklanduni.ac.nz.
