Champions League Streaker Plugs Russian Porn Site in Cheeky One-Piece

2:56 PM PT -- Guess who else was watching the Champions League final ... Daniel Kaluuya!!! We got the 'Get Out' actor -- who's British, BTW -- outside of the Village Idiot on Melrose, where he was rocking an Arsenal jersey and quickly gave us his take on the game.

Check it out -- sounds like he was rooting for anything but a Tottenham win. Ya know he's gotta be happy right about now.

The Champions League Finals just wrapped -- and while there was a lot of action ... the highlight might've been a model who risked it all to plug her BF's porn site on the field.

The streaker is suspected to be model Kinsey Wolanski, who's dating Vitaly Zdorovetskiy -- a guy who set up a Russian porn site that the two of 'em must really be passionate about ... 'cause she ran out onto the pitch in the first half in a skimpy one-piece with his site plastered in front.

Security was quick to give her a chase and escort her off the field, but not before everyone got a glimpse of her body-hugging outfit and some revealing shots ... from the front and back.

Gotta say as far as in-game interruptions go ... we don't really mind this one so much. Oh, and congrats to Liverpool for beating the Spurs -- heck of a game.