Brook and Khan have been in talks since the summer over a huge domestic bout for which British boxing fans have clamoured for years.
Khan told Express Sport earlier this week that he is considering an offer from pound-for-pound star and WBO welterweight champion Terence Crawford, however, which may scupper fight plans against the Yorkshireman.
The Bolton boxer said: “The Kell Brook fight is always going to be there – he’s not going to go anywhere. If I don’t fight Crawford, Crawford won’t be there again.”
Eddie Hearn, who promotes both Brook and Khan, issued a stern message to Khan, though, confirming that it is now or never for the Brook fight.
Brook has been preoccupied with preparation for tonight’s fight anyway, as he takes on Australian super welterweight Zerafa (25-2).
When Khan made his comeback this April after a 23-month hiatus, Brook, working on the Sky Sports punditry team, entered the ring afterwards and confronted the Bolton boxer regarding their long-term spat.
So, why is Amir Khan not returning the favour at the Sheffield Arena tonight?
Express Sport is on hand to fill you in.
Kell Brook: Why is Amir Khan not at rival’s Sheffield fight against Michael Zerafa?
Khan has decided to dodge the opportunity to analyse his potential opponent in the flesh because it is his birthday.
Now 32 years old, Khan said of the fight: “I’m not going to be going there – it’s my birthday on that day.
“I’m always on the go as well… I’m usually away in training camp so I thought: ‘Why don’t I spend it with my parents?’”
The former super lightweight world champion revealed his zeal to watch the fight, nevertheless.
“If it wasn’t my birthday then I probably would have gone,” Khan added.
“Sky have messaged me if I liked to work on it, so I didn’t respond back. I text [head of Sky Sports Boxing] Adam Smith: ‘What date is it?’ Just to let him click on.
“I’ll watch it, obviously, I’ll watch it. I’m a boxing fan as well, it’s always good to see who you might be fighting next. So I’ll watch and break it down a bit myself.”