Anthony Rizzo's World Series Ring Rescued From Bottom Of Lake Michigan

Anthony Rizzo almost lost his World Series ring at the bottom of a massive lake ... but fortunately for the former Cubs superstar, a famed Chicago diver saved the day.

Yohei Yamada -- an experienced swimmer who makes a living helping those retrieve items they've lost in Lake Michigan -- told Block Club Chicago he once gave Rizzo a big hand when it came to his championship bling.

Yamada explained Rizzo's hardware had slipped off his hand after he had lost some weight ... and once it disappeared in the water, the baseballer called Yamada for an assist.

Yamada strapped on his wet suit and dove in -- and somehow found it. He revealed Rizzo later rewarded him with a big tip for the retrieval.

Rizzo, of course, earned the ring back in 2016 -- when he helped the Cubs knock off Cleveland in Game 7 of the World Series.