Jay Z & Beyonce -- Couples Fight Night ... At Muay Thai Boxing Match

In what seems like a scouting trip for a possible Solange Knowles career change, Jay Z and Beyonce took in a Muay Thai fight during their vacation in Thailand.

It all went down at Patong Boxing Stadium in Phuket. There were kicks. There were punches. There was Beyonce sitting ringside while the violence unfolded ... all in a space that was roughly the size of an NYC elevator.

FYI -- Muay Thai is the national sport of Thailand ... where fighters are allowed to use their knees, elbows, feet, shins and hands to strike their opponents.

High heels are strictly prohibited.