Audley Harrison told Ringside that he has rediscovered his mojo and will be right on his game when he enters this Saturday's Prizefighter.
The southpaw, who was floored by David Price inside a round in his last bout, won the eight-man competition in 2009 after beating Scott Belshaw, Danny Hughes and Coleman Barrett.
Harrison, who plucked Olympic gold 13 years ago in Sydney, says he will "prove himself" again inside York Hall this weekend - and, if he gets the chance, defeat Martin Rogan, who he lost to on points in 2008.
"I have talked the talk but I haven't always walked the walk as a professional," said Harrison, who was beaten by David Haye in 2011 when he battled for the WBA heavyweight title.
"I was lost in the wilderness like a blind man without a cane and walking around with a broken heart after I lost my (BBC) contract in 2004, but I have fallen back in love with boxing."
"After I got knocked out in a round by Price people thought: 'This guy has definitely gone' but I told myself to get back up because I was looking so good in camp, and to put in special performances, like when I won Olympic gold, you have to tick boxes (and have bad days)."
Harrison, who will tackle Dane Claus Bertino in his opening contest in Bethnal Green, added: "When I won Prizefighter I was at 50 per cent and the level of competition wasn't that high; the guys didn't understand the format and didn't pace themselves.
"This time there is a great line-up and it will be tough, but I want it that way because I want to prove myself on Saturday night - and get revenge on Rogan; potentially meeting him in the semi-finals is really getting my juices going.
"I have 100 per cent respect for him as he is a comical guy, tough and goes for it in the ring - but I'm definitely going to walk through him. My spirit is up and my journey is not over."
Ulsterman Rogan, who joined Harrison in the Ringside studio, won the inaugural Prizefighter in 2008 and said his solid graft in the gym will ensure he lifts the trophy again.
"There are always fireworks when I'm involved, but I am fresher and better than five years ago when I was totally inexperienced," said the 41-year-old, who was conquered by Tyson Fury in April last year.
"I have since beaten Audley and Matt Skelton and I am working harder, training harder and hitting a lot harder. I'm going to win it again."
Watch Prizefighter: The Heavyweights from 8pm, Saturday, Sky Sports 1 HD.