FRANCIS NGANNOU revealed he was still having medical tests a week after his brutal knockout loss to Anthony Joshua.
AJ finished the ex-UFC champion in two rounds following three knockdowns and one final ruthless right hand.
Ngannou was left needing oxygen following the finishing shot but spoke out on Instagram Live a week later to give fans an update.
He said: "I was conscious right after (the KO), and since then everything’s been good. I'm still going to run some medical work, just in case."
Ngannou, 37, had dropped Tyson Fury on his boxing debut only to lose a controversial split-decision in October.
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But Joshua, 34, helped restore order in the ring just five months later with his emphatic finish.
Ngannou - now 0-2 as a boxer - revealed he was "falling asleep" while warming up to fight AJ as the bout did not start till 3am in Saudi Arabia.
He said: “Leading up to that fight, it wasn’t my day.
"Not to say the result would have been different but it wasn’t my day. At any moment of the day, I felt like I wasn’t good to go.
“Even in the locker room, trying warm up, it wasn’t going well. I was falling asleep. I was sweating but I was falling asleep.
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"That’s why I took some time out for me, some time to reflect on everything that happened to me.
“Heads up to Anthony Joshua, they did everything right. Heads up to my team too, we did everything properly but I didn’t execute the plan because I didn’t feel present.”
Ngannou walked out on the UFC and put his MMA career on hold to make the lucrative switch to boxing - which ultimately banked him around £20million.
He instead signed for the Professional Fighters League but insisted his business in boxing is not yet over.
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Ngannou said: “I am not done yet. The only thing missing here was time.
"I will take some time for myself to chill, then come back to training to get ready for another challenge.”
