On a Sunday night, Floyd Mayweather — not for the first time his career — left fight fans stunned.

The undefeated boxer announced he’d be once again leaving retirement to fight Tenshin Nasukawa in RIZIN on December 31 of this year. The rules and weight class are yet to be set, as well as various other background context to the shocking announcement.

Check out with some of Mayweather’s fellow fighters had to say on the matter:

Floyd switched a fight up quick when khabibs name got mentioned 🧐

— Jarred Brooks (@The_monkeygod) November 5, 2018

Stop it https://t.co/Jr75oYE4VE

— Jake Ellenberger (@EllenbergerMMA) November 5, 2018

Wow!! Japan doing big thangs @FloydMayweather vs @TeppenTenshin #RIZIN14 12.31 pic.twitter.com/iSRoX0SORD

— Jessica Jag Aguilar (@jagatt) November 5, 2018

Wow! Floyd Mayweather to Japan to fight @RizinFF?!

— #CyborgNation #UFC232 (@criscyborg) November 5, 2018

😲
Super announcement for @rizin_pr today.@floydmayweather and @tenshin.nasukawa nye.
Congrats @nobu_sakakibara #rizinff #rizin2018 #japan #mma pic.twitter.com/uEDOjafviI

— Gabi Garcia 🥇 (@gabijiu) November 5, 2018

😳😳😳 https://t.co/BXArDSEWOQ

— Rafael dos Anjos (@RdosAnjosMMA) November 5, 2018

–