Blackwell, 26, was involved in a gym sparring session just months after being told his career was over due to a brutal defeat to Chris Eubank Jnr that ultimately put the Trowbridge man in a coma last March.
Despite weeks of worry and fundraising by the boxing community, Blackwell has found it tough to shake off the will to box and now has another mountain to climb in order to get his health back.
“This is not a quick process, we are looking at several months,” Lockett told BBC Radio Wales before turning his attention to the others present when Blackwell was allowed to take blows to the head despite his permanent condition.
“I can’t believe the boxer he sparred with, and the coach or coaches involved, would ever allow Nick to spar when he’s had a brain injury,” he said.
“In due course, I hope they are dealt with by the British Boxing Board of Control in the correct manner.”
The Board are due to meet in January to comb over evidence from an investigation into the matter and hope Blackwell is well enough to present his own case by the time the review takes place.