Woodhall, the World Boxing Council super-middleweight champion, has put a seven-figure price tag on a showdown against Calzaghe, the World Boxing Organisation holder, and Catley stands in the way of Woodhall and financial security for his young family.
Having had the preparations for his first defence upset by a change of location and a revised date, as well as suffering a pay cut and being presented with a changed and different-style opponent in Catley, it would be understandable if Woodhall has gone a trifle off the boil.
But the champion is too professional to allow his focus to become clouded against Catley, the British middleweight champion who has moved up a weight, who could be a handful early in a fight which, for him, has come from nowhere.
"There's Robin Reid and Dean Francis in the super middles, but Calzaghe is the only one that really interests me," said Woodhall. "Unification with Calzaghe is what everyone wants to see. I strongly fancy my chances."
Woodhall was set to earn pounds 400,000 for defending his title against the Italian southpaw Vincenzo Nardiello in Sicily in July, but will get substantially less for tackling Catley.
When the American promoter Don King lost the right to stage Woodhall's first defence because of contractual delays, the Nardiello bout was moved to Telford, then Nardiello pulled out with an injury to hand Catley, who has 22 wins from 24 fights - with 17 inside the distance, his big opportunity.
"I've done all my training to face Nardiello, a southpaw, but Catley is orthodox," added Woodhall. "But I'm the champion of the world and, if I can't handle Catley, then I can't handle anyone.
"He is certainly more powerful than Nardiello and, if I stand toe-to- toe with him, I will come unstuck. I have got to keep him at long range and make sure I don't get drawn into a war with him. It's annoying that I'd prepared to face a southpaw but I've just got to get on with it."
Catley was ranked a modest 19th among the middleweights in his division, yet he has been cleared by the WBC emergency committee to fight Woodhall to keep alive Frank Warren's show and Sky television date.
"It's the opportunity of a lifetime," Catley said. "I know I'm going to be classed as the underdog, but I've sparred with Steve Collins and I don't believe there is anyone tougher to spar with than him."