Jake Paul vs. Anthony Joshua is actually real — the fight is set to go down in a matter of weeks!!

After his matchup with Gervonta Davis was scrapped, El Gallo will now face the former heavyweight champion in a professional bout on December 19 at the Kaseya Center in Miami … and Netflix will be streaming the whole thing.

Joshua is by far Paul’s biggest challenge to date — he’s not in his 50s (he’s 36), he’s not a former MMA fighter, and he’s not washed.

Joshua has a 28-4 record … with 25 of his wins by knockout. He’s still active … with recent wins over Francis Ngannou, Otto Wallin, Robert Helenius, and Jermain Franklin.

While his most recent bout was a loss, it wasn’t to a scrub by any means — he fell to Daniel Dubois with the IBF heavyweight title on the line.

TMZ Sports actually spoke with Joshua’s promoter, Eddie Hearn, in October … and he told us the two sides were quite interested in setting up a fight, but there were some business things in the way.

Hearn said the status of the Paul vs. Joshua bout really depended on what happened with Davis … but that was before Tank’s latest troubles torpedoed the Nov. 14 tilt.