Briedis received the Muhammad Ali Trophy after defeating Dorticos on Saturday in Munich, Germany, and on DAZN, with two judges scoring the fight 117-111 and the third having it 114-114.
Dorticos (24-2) was the aggressor but Briedis, a former WBC and WBO champion, landed the more noticeable blows with a number of right uppercuts to dethrone the IBF holder.
“It feels like a dream,” said Briedis (27-1), whose only professional defeat has come against Oleksandr Usyk in 2018.
Meanwhile, world champion Josh Taylor retained his WBA and IBF light welterweight belts thanks to a first-round knockout of Apinun Khongsong.
Taylor’s body shot sent his undefeated opponent to the canvas in incredible fashion at York Hall in London.
“I felt it [the punch] sinking in straight away,” Taylor told BT Sport. “I didn’t know it had hurt him to that extent until I saw him on the floor.
“He [Khongsong] was the heaviest puncher I have ever been in with. I could feel the weight of his power. That switched me on to take my time and be patient.
“It was a great shot but I’d like to have shown what we’ve been working on in the gym. But you don’t get paid overtime. I can go and get a pint and a pizza.”
