The pair - who will collide on Sky Sports Box Office at the AO Arena in Manchester - are fighting at a catchweight of 149lbs - two pounds over the welterweight limit.
Despite both fighter's being past their peak, it is certainly a fight that can be labelled as better late than never.
No world titles are on the line but there is something worth more than that in this fight - pride.
The winner will be remembered for ending one of British boxing's all-time grudges while the loser won't be able to walk the streets without being reminded about the defeat.
Khan has been inactive since 2019 and was last in action against Billy Dib, who he stopped inside the distance in Saudi Arabia. Meanwhile, Brook is returning for the first time since his defeat against Terence Crawford in 2020.
Both men are 35 years old and it is set to be an intriguing contest with many unable to call a winner.
Below, we take a look at five key elements to the fight.
Brook is not cumbersome by any measure but his opponent's rapid hand speed and footwork, his ability to get in and out of danger and crucially get off the first punch - the jab could be crucial for Khan - is well noted.
Khan, a former unified light-welterweight champion, may not be as quick as he once was and there were signs he was slowing down against Terence Crawford in 2019 but he is still likely to be the faster of the two.
Khan's ability to overwhelm his foes with punches they do not see coming has largely been responsible for the 21 stoppages he has gained from his 34 wins to go with five defeats, but Brook is more heavy-handed.
This should not be billed as 'speed v power', which is too simplistic. Certainly on the world stage, former IBF welterweight titlist Brook (39-3, 27KOs) has relied as much on timing as he has done on outright obliterating previous opponents.
Khan was renowned for leaving himself wide open in the first half of his career but his work with ex-trainer Virgil Hunter brought out a more pragmatic side.
Still, Khan remains vulnerable to being clipped. Brook, the bigger of the two fighters, arguably has the sharper ring IQ and a more varied set of skills.
But this is the bout he has coveted most for a while now so when the sell-out crowd are cheering and the blood is pumping, will he be drawn into a war?
Khan's swiftness has meant he has been able to set a high tempo and he has rarely shown signs of gassing as a fight wears on.
Of the two, Bolton-born Khan is more committed to staying on top of his fitness, with Brook often ballooning in weight between fights.
Boiling down to welterweight has proved difficult in the past for the Yorkshireman and, while he has two extra pounds to play with, how he gets down to the weight could be instructive.
Khan has suffered some devastating knockout defeats, most notably against Breidis Prescott early on in his career and then Saul 'Canelo' Alvarez following an ill-advised leap to middleweight.
But Brook's three losses have all been inside the distance. Setbacks against Gennadiy Golovkin and Errol Spence Jr necessitated surgery and metal plates to fix breaks in both eye sockets while he was stopped on his feet by Crawford in his last outing.
There is a reason why fans have been clamouring for this fight for several years: no-one can say with any degree of certainty who will come out on top.
This fight may not have the prestige it undoubtedly would have had when Brook ruled as a 147lb world champion from 2014 to 2017 but both fighters being shop-worn adds an element of intrigue to proceedings.
The victor could receive one more world title shot but there is nowhere for the loser to turn.