Pedro Mendes feared he could have suffered long-term injuries after being hospitalised following a horror challenge by Manchester City's Ben Thatcher.
Mendes was knocked unconscious by Thatcher's forearm challenge which saw the Portsmouth midfielder crash into advertising hoardings during the second half of Wednesday's goalless draw.
The former Tottenham star then suffered a partial fit by the side of the pitch and required oxygen on his way to hospital.
"The moment was terrible," the 27-year-old told British media on his release from hospital.
"After the incident my head crashed into the fence and I do not remember anything after that until I was in hospital.
"At first I had real fears about possible after-effects of the incident but the doctors told me they are optimistic I will be okay. I am a strong person and one day I hope to forget what happened.
"But this is the worst thing that ever happened to me in my career. It is the hardest to deal with." PA
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