Francis Ngannou is mourning the tragic death of his 15-month-old son

He wrote on Instagram: "Too soon to leave but yet he's gone. My little boy, my mate, my partner Kobe was full of life and joy.

"Now, he's laying without life. I shouted his name over and over but he's not responding.

"I was my best self next to him and now I have no clue of who I am. Life is so unfair to hit us where it hurts the most.

"How do you deal with such a thing? How can you live with it? Please help me if you have an idea because I really don't know what to do and how to deal with this."

The 37-year-old fighter also took to X, formerly Twitter, to shared a different message about grief.

He asked: "What's the purpose of life if what we're fighting tooth and nail to get away from is what finally hit us the hardest!?

"Why is life so unfair and merciless? Why does life always take what we don't have? I'm f****** tired."

Francis' fans, friends and fellow MMA and UFC fighters have sent their condolences during such a gut-wrenching time.

Conor McGregor replied: "I am so sorry to hear of your loss Francis, my prayers are with you and your family at this time."

And Francis' coach Erick Nicksick asked everyone to keep the star and his family in their hearts, as he urged people to "say I love you more often".

He tweeted: "It's been a heavy few days, words can't express the pain we all feel for the Ngannou family during this time.

"Please keep Francis and his family in your heart, and may this be a reminder of the fragility of life. Say 'I love you,' more often, tomorrow isn't guaranteed."

Francis first rose to fame in the Ultimate Fighting Championship (UFC) where he held the UFC Heavyweight Title and racked up a 12-2 record.

In boxing, he lost to Tyson Fury in a controversial split decision, before losing to Anthony Joshua by knockout last month.