Logan Paul took an L Saturday night in his fight against KSI ... but it was not without controversy.
Logan lost to KSI in a split decision at the Staples Center in L.A. ... in a highly anticipated boxing rematch. They went toe-to-toe for 6 hard rounds.
KSI did the early damage with some ferocious body shots, but things started to turn for Logan in the 3rd round when he started landing body punches of his own.
Paul caught KSI with two huge uppercuts in round 4 that sent him to the canvas, but held his head on the way down and seemed to land another punch.