Isaac Chamberlain: ‘There was coke down my leg and I knew I had to get out of that life’

“As soon as it gets into your head you have to block it,” Isaac Chamberlain says as he brushes aside a dark and brooding thought of what defeat might mean for either himself or Chris Billam-Smith when they meet in a Commonwealth and European cruiserweight title fight in Birmingham on Saturday night. It is one of the most intriguing British bouts of the year as Chamberlain steps into the champion’s home town for a contest fraught with risk and danger.

We sit on Chamberlain’s bed in the house he has rented for his small team in Birmingham. It feels a long way from Brixton, where he grew up amid poverty and strife, drug-running and knife crime, but Birmingham has been the site of Chamberlain’s fight-camp for six weeks. He is 28, a doting father to a little boy and perhaps the most thoughtful and generous boxer I know. Chamberlain also writes, voicing his doubts and fears with vivid eloquence , as he reflects deeply on life.

Since becoming a father, and feeling so much happier and more settled, there has been no need to articulate his pain as he had done previously in passionate bursts of writing. Now, approaching his 16th bout, Chamberlain knows that victory over Billam-Smith could deliver the world title shot he has dreamed of for years.

They have each lost only one fight and, while Billam-Smith has been the more active boxer in recent years, this is the biggest opportunity of Chamberlain’s career since he and Lawrence Okolie headlined a bill at London’s O2 Arena in 2018. A points defeat that night derailed Chamberlain for a long time but he now has another chance to reach world championship level.

His training has been gruelling and Chamberlain is pining for his eight-month-old son, Zion, whom he won’t see until after