Fans are clamoring for a domestic grudge fight between Amir Khan (32-4, 20 KOs) and Kell Brook (37-2, 26 KOs).
But the contest may not happen until the mid-point of 2019, according to Matchroom Sports founder Barry Hearn.
Both boxers are promoted by Matchroom, who hope the two fighters will eventually collide in the ring.
One of the stumbling blocks is the weight.
Khan currently competes in the welterweight division, while Brook is now campaigning at the junior middleweight limit of 154-pounds.
Hearn believes the two boxers are likely going to pursue world titles in their respective divisions - and then collide in the ring.
Both of them are currently being called out by the top names in their weight classes.
"You have a Mayweather-Pacquiao situation where the fight could have happened already, should happen really quite soon, and may not happen for another 12 months," said Barry Hearn to Sky Sports.
"I think egos, personality, and the weight differential, because Khan is saying 'I want to box at 147', Brook is saying 'I'll make 147'. I don't think we should let him [Brook]. I don't think he's the real ticket at 147.
"At 154, we would argue, don't take it, to Amir, because he's not a 154 fighter. Whether there's a compromise at something like 150, and we can do the fight. I get the gut feeling that it will come after they've had their respective world title challenges in their respective weight divisions first."
While both are promoted by Matchroom, Hearn says it's ultimately the decision of both boxers on whether or not they will face each other.
The fear, says Hearn, is one of them suffered a loss in their title quests - because a loss to either boxer will drop the value of the contest.
"They have choices. The choice is - financially that they should fight each other at some catchweight compromise, because it's a huge fight for the British public, sells out a stadium, is a massive pay-per-view," Barry Hearn said.
"The choice for them is - do they go and pursue their own career at their own respective weights on the understanding that fight can still happen at some time in the future. Unfortunately in boxing, a defeat for either devalues that fight."