Brad Lesley Dead -- 'Little Big League' Star Dies at 54

Brad Lesley -- who played a few years of Major League Baseball before appearing in a slew of '90s sports movies -- passed away this weekend. He was 54.

Lesley's ex-wife, Chiho Svimonoff, tells TMZ ... Lesley had been suffering from kidney problems and had been living in a nursing home for the past seven months, where he was receiving dialysis.

Svimonoff says Lesley was rushed to a hospital in Marina Del Rey on Saturday night and ultimately died from kidney failure.

Lesley played for the Cincinnati Reds and Milwaukee Brewers from 1982 to 1985 before switching to acting. In the '90s, he appeared in "Mr. Baseball," "Space Jam" ... and, of course, he played that angry pitcher with the goatee in "Little Big League."

R.I.P.