Wrestling Star Lanny Poffo Dead At 68, 'Hacksaw' Jim Duggan Mourns Loss

Former wrestling star Lanny Poffo -- younger brother of the late Randy Savage -- has died ... his friend, "Hacksaw" Jim Duggan said Thursday.

He was 68 years old. A cause of death is unknown at this time.

Poffo made his in-ring debut with the All-South Wrestling Alliance in 1974 ... before joining multiple promotions affiliated with the National Wrestling Alliance, where he won a Tag-Team Championship alongside his father, Angelo.

In 1985, Poffo joined the World Wrestling Federation ... where he would be known as "Leaping Lanny Poffo" and "The Genius."

Poffo competed against huge names like Andre the Giant, Hulk Hogan, Jim Neidhart and The Ultimate Warrior over the course of his stellar career ... and at one point, teamed up with Mr. Perfect.

Poffo inducted his brother, Randy, into the WWE Hall of Fame in 2015 ... giving a touching tribute and attending WrestleMania 31 in his honor.

Out of the squared circle, Poffo also wrote several books ... and was known for writing poems.

"With a very, very heavy heart, I've been asked to let everyone know about the passing of our friend and colleague Lanny Poffo, The Genius," Hacksaw said on Instagram.