Konta was increasingly hampered by an abdominal problem towards the end of the first set and received a first medical timeout while serving at 5-4 for the opening set.
She returned to court with her stomach partially taped up, saved a breakpoint and took the set before receiving further treatment on her abdomen and hip in the set break.
But the issue continued to hamper her and, after losing the subsequent two games, the No13 seed and former Australian Open semi-finalist, retired from the match with immediate effect and left the court in tears.
And Konta said: “I pulled my ab and that made it difficult for me to serve and so that’s why I had to retire. I feel like I’m in a bit of shock so I don’t really know anything.
“I felt it in my second service game of the first set so I was conscious of trying to adapt. I was starting to be aware of it. I tried to manage it as best I could. I don’t have answers for you why this happened. I haven’t had an ab issue in a very long time.”