Liam Hemsworth -- REBOUNDING IN VEGAS ... Major Flirting With Hot Chick

Call him Dennis Rodman, 'cause Liam Hemsworth was rebounding like a CHAMP in Vegas last night ... spittin' some serious game to a smokin' hot chick -- and from the looks of things, it worked.

Just one day before reps "officially" announced the demise of his engagement to Miley Cyrus, Liam and 5 of his friends hit up XS Nightclub ... where he ran into 23-year-old Eiza González.

FYI -- Eiza happens to be a singer/actress (seems like someone's got a type).

They drank ... he smoked ... they flirted ... they were thisclose ... and people in the club said they never left each other's side before leaving the joint together at 2 am.

Muy bien.