Chelsea doctor Eva Carneiro has decided to leave the club - six weeks after criticism from manager Jose Mourinho.
Chelsea asked Carneiro, 42, to return to work, but she has decided not to and is now considering her legal position.
The Football Association is looking into a complaint that Mourinho used abusive or sexist language towards her.
Chelsea say they do not comment on internal staffing matters.
Heather Rabbatts, chair of the FA's Inclusion Advisory Board, expressed her "sadness and anger" at the news of Carneiro's departure.
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Carneiro and head physio Jon Fearn went onto the pitch to treat midfielder Hazard in the closing stages of the draw with Swansea.
It meant the Blues were temporarily reduced to nine men, with goalkeeper Thibaut Courtois having been sent off, and Mourinho said the duo had been "impulsive and naive".
Carneiro lost her place on the bench and was no longer allowed to attend matches or training sessions.
Two days after the incident, she posted a message on Facebook thanking the public for their "overwhelming support".
Mourinho stood by his decision to remove her from her role, adding he had a "good relationship" with his medical staff.
'Her departure raises a serious question'
Rabbatts, the FA's only female board member, has been vocal in her support of Carneiro, whom she said acted "properly".
"Her departure raises a serious question on how players are safeguarded if their medical support is compromised," said Rabbatts.
"The footage of the abuse she has endured in silence from the stands during her career is something we should all be ashamed of.
"I hope that Eva's own situation can be resolved quickly and positively and that she will be able to continue to work in a senior position within the game."
The Women in Football group said Carneiro was highly respected and it was "bitterly disappointed" about her departure.
"We believe it is appalling that her professionalism and understanding of football were subsequently called into question by manager Jose Mourinho and it threatened to undermine her professional reputation," said a spokesperson.
"We also believe that Dr Carneiro's treatment and ultimate departure from Chelsea FC sends out a worrying and alienating message to the already small numbers of female medical staff working in the national game."
|Who is Eva Carneiro?|
|Carneiro is a 42-year-old sports medicine specialist who was born in Gibraltar|
|She studied medicine at Nottingham University and completed her MSc in Sport and Exercise at Queen Mary University of London|
|Carniero previously worked at the British Olympic Medical Institute, with England Women's Football and UK Athletics, before joining Chelsea in 2009|