Kell Brook has fired out a final warning to Amir Khan, saying a fight between them has to be done this year.
Sheffield star Brook admits he could walk away from the sport at the end of 2018, but first wants to meet his bitter rival in the ring.
Khan suggested on Wednesday that Brook is one of his potential opponents in 2018, after signing a three-fight deal with Matchroom, but Brook has told him to stop "talking this nonsense" and finally agree to fight him.
I don't want to be talking this nonsense with Khan, him saying he wants it next year or whenever. It's got to happen pretty soon or I am done.
"We need to agree on a fight this year because I don't know if I will be boxing into next year, if I am honest," Brook exclusively told Sky Sports.
"I really do mean it. I am not getting any younger. I want a great year this year, no messing around, no play-time, I want big fights under my belt.
"I don't want to be talking this nonsense with Khan, him saying he wants it next year or whenever. It's got to happen pretty soon or I am done.
"I would just love to test myself against him. It will probably bring the best out of him and we will give something back to the fans for helping us throughout our careers.
Khan back on Sky Sports
Amir Khan has signed a three-fight deal with Matchroom and will be back in April...
"We'd perform like mad men in the gym and we'd come together and fight each other.
"There is only one - him. I will tell you now, there is only one fighter who will fire me up and that's the one."
Brook is in Fuerteventura preparing for his first fight at super-welterweight in March, against Sergey Rabchenko, and was told about the Khan deal on Tuesday night.
The 31-year-old was not surprised to hear the news and is even looking forward to being ringside when the Bolton star makes his British homecoming in Liverpool on April 21, live on Sky Sports.
"He hasn't boxed for a long time and Matchroom make things happen and make big fights in Britain, so I wasn't at all shocked," Brook said.
"It is a bit strange but that's where it will end. We have got the same promoter and that's it. Now he fights for Matchroom, finally we will see me and him in the ring.
"And it's very possible I will be ringside. He was in Sheffield for one of my fights, so I could well be there, now we're both Matchroom.
"The fireworks could start. I might turn up for that, I might even jump in the ring and lay a chocolate brownie on him.
"No strawberries... chocolate brownies only."
Watch Kell Brook fight in Sheffield, on March 3, and Amir Khan, in Liverpool, on April 21, both live and exclusive on Sky Sports.