Nathaniel Collins has revealed he had to undergo eight-hour surgery to correct a life-threatening issue after being left in "unbearable pain".

The undefeated 15-0 boxer - current BBBofC British Feather, Commonwealth Boxing Council Feather and EBU EIlver Feather champion - announced he was recovering in hospital after having to undergo life-saving surgery over a twisted bowel.

Collins, 27, from Bearsden, was rushed to hospital on Monday, May 21 after pain in his abdomen and sternum was causing his body to "shake and convulse uncontrollably".

The boxer - nicknamed The Nightmare - was raced into hospital for medical treatment with major emergency surgery required in a horror eight-hour-plus period in theatre.

Thankfully, surgeons managed to untwist and repair Collins' bowel and repair the damage caused by the health scare.

Collins remains in hospital to recover from the terrible ordeal and has shared images of himself smiling with family despite still being in pain and discomfort.

He posted on Instagram: "Thought I would post a quick update as very few people know & everyone is wondering why I am so quiet/not got back to them.

"Monday 21st of May i got rushed to hospital after experiencing unbearable pain in my abdomen and sternum which was causing my body to shake and convulse uncontrollably.

"After getting to the hospital and receiving tests the doctors detected I had a twisted bowel and deemed it life threatening.

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"Due to this I was taken up to the theatre and underwent major emergency surgery for 8+ hours to untwist my bowel and repair the damage. Thankfully surgery went well and I am currently recovering in hospital. Just making this post so people aren’t worrying i am not getting back to them.

"I feel very grateful to the surgeon who helped save my life. He made such a conscious effort to do as much damage control as possible. Also a huge thank you to all the staff helping look after me here.

"Still in alot of pain and discomfort but hopefully have more news on my recovery/next steps soon."