Hayden Panettiere and BF Brian Hickerson Get in Massive Brawl with Bar Patrons

Hayden Panettiere and her boyfriend Brian Hickerson look less like lovers, and more like tag-team partners after getting into a huge melee at a famous Sunset Strip hotel.

We got this insane video from Thursday night outside the Sunset Marquis where HP, and mostly Brian, threw down with a large group of people. At one point, security was able to calm the situation ... but then Brian broke free, ramping things up again.

An eyewitness tells us everything started inside at the hotel bar, where some sort of argument started between Hayden, Brian and some other patrons. We're told one of the people from the other group claimed Brian spit on them, and the manager kicked everyone out ... leading to this wild scene on the street.

During the fight, you can see Hayden do her best to try to pry Brian off the others -- and it even appears she gets kicked in the face while she was in the scrum. She's heard yelling, "Brian, jail!" ... likely warning him what could happen if cops show up, because he's on probation until 2025.

Once everyone finally gets separated -- Brian and Hayden head back into the hotel -- where she apologizes to staff, and the other group leaves.

Hayden and Brian certainly have a tumultuous history -- he's been arrested for domestic violence and assault for alleged attacks against the actress. Last night, at least, they were a united front.