Conor McGregor was linked to a potential cross-sport summer showdown with retired boxing legend Floyd Mayweather last week, but UFC president Dana White quickly shot down the tabloid report.
However both athletes are seemingly keen fuel to speculation, with Mayweather declaring the fight is "possible" and UFC superstar McGregor also teasing the possibility of the showdown.
McGregor has previously said he'd be open to fighting the undefeated 39-year-old boxer, and it's easy to see why.
A Mayweather-McGregor bout would destroy every single pay per view record, and two men who are very focused on making money would walk away with gigantic checks.
McGregor took things a step further Sunday, posting a Mayweather-McGregor fight poster on his Twitter page.
Mayweather, who walked away from the sport of boxing after his 49th victory, recently filed for trademarks on the terms TMT 50" and "TBE 50."
And Floyd Mayweather Snr confirmed his son was in talks to box "some MMA fighter" a day after The Sun's exclusive story.
Now the retired five-weight world champion has refused to rule out the highly-anticipated fight and even told fans to "keep your fingers crossed" for the "possible" superstar showdown.
Speaking before Amir Khan's WBC middleweight title loss to Saul Alvarez in Las Vegas Mayweather said of fighting McGregor: "It's possible you know.
"It was a name that was shot at me but the rumour that ya'll been hearing - the rumours that I started - may not be a rumour, so keep your fingers crossed.
"It may be a boxer versus an MMA fighter."
Mayweater again declared he would not fight for less than nine-figures.
"You already know my number," he said.
"Every time I go out there and compete at the highest level, my number is of course $US100 million or better. I feel like I can demand that because I've broken all records in the sport of boxing."
Mayweather confirms McGregor fight is possible