The 27-year-old, who squares off against Witter for the British welterweight title at the York Hall in London, believes that he has finally overcome a turbulent time in his personal life.
"Today, my head's in a real good place. I've no worries," said Gavin.
"My mum was ill but everything is good now. I've had a difficult year in my personal life, but that's all sorted. I'm not looking at the past, I'm looking to the future and I'm really excited about what is ahead.
"This is my moment to step up and prove that I'm the real deal. Boxing is on a high at the moment and I want to put my name up with the likes Carl Froch and Ricky Burns."
Gavin is targeting a European title match should he overcome the Sheffield fighter.