Dan Bilzerian claims someone jacked his luxury timepiece right off his wrist during the Canelo Alvarez boxing match in Las Vegas ... and now the cops are involved.
The playboy poker player tells TMZ ... he was wearing a Richard Mille watch, valued between $950k and $1 million, to the Canelo fight and at some point, he noticed it went missing from his wrist.
Dan says he was taking a bunch of photos with fans as he walked toward the ring, and thinks someone may have slipped it off his wrist in the scrum because the carbon fiber watch is very lightweight and doesn't have a lock on the clasp.
Law enforcement sources tell TMZ ... police took a larceny report and cops will investigate.
Dan says he filed the police report right after the fight Saturday night, and now he's offering a $50,000 reward for any folks who can provide information leading to the watch's return.
DB tells us he didn't have the watch insured and the fight venue wasn't able to pull any surveillance footage from the fighter walkout area, which is where he believes the watch was taken.
Dan's hoping the reward money might spur someone to come forward with a video of when people were surrounding him, and he thinks there's a chance the alleged thief was caught on camera.