Conor Benn has been branded as a "coward" by Florian Marku, who accused his British rival of strengthening his unbeaten reputation with weaker opponents.
'The Albanian King' returns to action against Rylan Charlton on Saturday night on the David Avanesyan vs Josh Kelly bill, live on Sky Sports, with Benn watching from ringside as part of the Sky Sports team.
Even before he steps between the ropes, Marku has fuelled his heated feud with Benn, by given a scathing assessment of the 24-year-old welterweight's perfect professional record.
"I'm not like Conor Benn, who chooses people who have lost six, seven, eight times," Marku told Sky Sports.
"No, my opponents are undefeated. They don't give their loss easy."
Benn produced a career-best win in his last fight against Sebastian Formella, who had only previously been beaten by Shawn Porter, a former world champion.
But Marku was unimpressed and issued a stinging reply when told to describe Benn in one word.
"Coward," he told Sky Sports.
Marku endured the first blemish on his record in December, having been held to a hotly disputed draw by Jamie Stewart, although he has still vowed to dominate the division.
"In my mind, I'm the best. I don't feel like nobody is better than me," he said.
"I don't care what the people say. The people can say whatever they want.
"For me, I'm very confident, and if you're not confident in the game like boxing, you're in the wrong sport. I go in there, I don't think that the other guy can beat me. I don't think one per cent like this."
Charlton displayed his threat in his last fight, a crushing knockout of undefeated prospect Joe Laws, but Marku has urged his big-hitting opponent to stand and trade.
"About Rylan Charlton, I think that he's strong. Not stronger than me, never," said Marku.
"He's too slow for me, for my style. Not technical. He has only hooks and uppercuts.
"You cannot show your technique with someone that is running. If you see, all my opponents was running in the ring with me. Nobody stayed close to have a fight. I hope Rylan stays there and I can show my boxing skills."
Kelly is Benn's No 1 target?
Benn has previously suggested Kelly is 'the only fight I'm interested in', but questioned whether the former Team GB fighter can withstand the aggression of Avanesyan in their European title fight.
"It's going to be a hard one for Kelly," Benn told Sky Sports.
"But if he lives up to the hype and praise that everyone gives him, he'll come through with flying colours and really show what he is made of. He will rise to the occasion.
"But Avanesyan is an animal.
"Mid-to-late rounds, Avanesyan stoppage or Kelly will out-box him. It depends how Kelly moves on the night."
Watch David Avanesyan vs Josh Kelly on Saturday night, from 7pm on Sky Sports.