Floyd Mayweather's advisor has compared Saturday's fight between his protege Gervonta Davis and Britain's Liam Walsh to the night Mayweather overcame Arturo Gatti.
At London's Copper Box Arena, the American makes the first defence of his IBF super-featherweight title while fighting for the first time outside the USA.
The 22-year-old Davis established himself as a fighter of potentially the highest calibre when he won his title by stopping Puerto Rico's Jose Pedraza in January, and on Saturday against Walsh faces his greatest professional test.
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Leonard Ellerbe worked alongside Mayweather for the finest years of the retired fighter's career, those which included wins over Manny Pacquiao, Oscar De La Hoya, Shane Mosley and Ricky Hatton.
Each came when he was the world's leading fighter and a significant attraction in Las Vegas, but little over two years before beating De La Hoya he stopped the late, tough Gatti where he was such a popular figure in Atlantic City in six rounds.
That performance remains among the finest of a career in which many fights went the distance, and in his retirement Davis has perhaps become Mayweather Promotions' biggest hope.
"In June 2005, when we went to Atlantic City to fight Arturo Gatti, it was two totally different fighters, but a similar situation," Ellerbe said.
"These are the kind of fights you need to become a complete fighter. To be able to travel, go over to foreign soil, in front of (the opponent's) fans, and be able to come out and put on a spectacular performance: it prepares you for the next step.
"Floyd's been very hands on with Gervonta in this camp, with the final preparations. These are the kind of things that are an advantage: certain little things you're able to go over and do, that make a difference in a tough fight.
"Our fighters are inspired (by Mayweather's presence). It's a great thing to have a (future) Hall of Famer, the best fighter ever in our eyes, to be hands on with the guys in the gym, give them advice.
"It's a great thing to be able to have Floyd hands on with these fighters: it goes a long way and really, really helps."
The undefeated Walsh, 30, fights for a world title for the first time, and almost five years after he was first scheduled to do so when he was involved in a car crash before a scheduled match-up with Ricky Burns.
Since then he has long appeared ready for a fight of significance without one materialising, and asked if it felt like he had been preparing for Saturday's for five years, he responded: "Yeah, that's more than fair.
"I thought it was going to be a lot easier to get to this point, but I've always dreamed of being a world champion, and the focus has always been a title. Everything else along the way has just been stepping stones towards a world title.
"You get setbacks, knockbacks. The men at the top are usually the ones with the most defiance, the most will, and you've just got to keep going through it: that's boxing.
"It's really important (I don't get anxious now I finally have my chance). It's something I've dreamt of since a kid; it's important not to get emotionally into it, but it's a huge occasion.
"It has (been a challenge), but more so on the night: that'll be the biggest challenge."
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