George Groves says former trainer Adam Booth "abandoned" him ahead of his first world title fight.
Groves (21-3), who lost his third and most recent world title fight against Badou Jack in September, parted ways with Booth in the lead-up to the first Carl Froch fight in November 2013.
"I asked Paddy [Fitzpatrick] to train me for the first Froch fight when I was 10 weeks out," Groves told Sky Sports.
"I'd had a bust-up with Adam Booth. I felt like my one pro coach had abandoned me -- as he had done time and time before -- but this time he'd done it just before a world title fight, which was hard to swallow.
"I thought, 'Alright, I don't need you anymore. I'll move on. I can either train myself or I can go with a trainer that I had a previous relationship with', which was Paddy.
"We had a good fight. It didn't quite go our way but we bounced from that fight to the next fight and the next fight."
Groves recently parted ways with trainer Fitzpatrick and teamed-up with Shane McGuigan this week as he looks to refresh his career, while former trainer Booth now works with Chris Eubank Jr.
"I wasn't going to have another fight with Paddy after the Badou Jack fight," Groves added.
"The romantic ending would've been a win, saying well done to Paddy for training a world champion, then parting ways and going to find someone who can get the best out of me.
"Paddy is a great coach with a wealth of experience but he was never going to be able to get the best out of me."
Groves has his first fight under McGuigan's guidance on January 30 when returns to the ring to take on Andrea Di Luisa (18-3).