Anthony Joshua should heed the warning signs after Carlos Takam was handed a late opportunity to snatch his heavyweight world titles.
The WBA 'super' and IBF champion has endured a turbulent training camp leading up to his next title defence, with Kubrat Pulev pulling out through injury less than a fortnight before the first bell was set to ring at the Principality Stadium in Cardiff on October 28, live on Sky Sports Box Office.
Joshua had been thinking of a lucrative rematch with Wladimir Klitschko in Las Vegas when he first returned to the gym a few months ago, but the Ukrainian opted for retirement instead of a repeat of their punishing encounter and Pulev was next in line for a shot at the titles.
At their first press conference, a translator had suggested that Pulev found the fight 'terrifying', a misunderstanding perhaps, but the Bulgarian's body failed him, even if his mind was sound, and in stepped Takam last night.
The France-based Cameroonian cuts a formidable figure, with a muscle-bound physique and steely glare, leaving opponents in no doubt that they must ready themselves for a demanding fight.
Current WBO champion Joseph Parker can supply a character reference of Takam's toughness after they shared 12 brutal rounds before the relieved New Zealander emerged with a points victory.
"What a great fighter Carlos Takam is," said Parker after his chin and stamina had been tested. "We said this was going to be a hard fight. I had to have my A-game.
Joshua has broken the resistance of all 19 of his previous opponents, although he could require a scalpel rather than a sledge hammer to gradually prise open Takam's tight guard.
Takam's concrete-like chin is renowned in the division and it has been shattered only once in a sole stoppage loss to Alexander Povetkin, while 27 knockouts in 35 wins shows that Joshua cannot disregard his own defences.
Up until this week, Joshua's training regime had been tailored for Pulev, a 6'4" tall jab-right hand exponent, and the champion now has little time to bring in sparring partners to replicate the squat, come-forward aggression of Takam.
Late replacements have posed serious problems in the past as Lennox Lewis would testify after he switched his sights from a routine defence against Canadian Kirk Johnson to Vitali Klitschko.
The Brit was dragged into a bloody dogfight before the Ukrainian was stopped on cuts, despite his defiant protests, and Lewis decided to choose the safety of retirement rather than a rematch.
Takam cannot be compared to Klitschko, but he has gratefully accepted his chance to exploit any mental turmoil in Joshua, who must swiftly refocus his mind on retaining his titles in front of an expectant 80,000 crowd.