Former Chicago Park District Supt. Ed Kelly and his lifelong friend Muhammad Ali. View Full Caption Ed Kelly

SOUTH CHICAGO — In 1972, the boss of Chicago’s flat-broke Park District launched a boxing program that only got off the ground thanks to an anonymous benefactor.

On Thursday, that former Park District superintendent, the legendary Ed Kelly, revealed a secret he's kept for 44 years: Muhammad Ali personally outfitted Chicago parks in tough parts of town with boxing gear.

It started at Bessemer Park in South Chicago. That's where Kelly made his first unfunded push to set up boxing training centers for “the sweet science” in parts of town where kids didn’t particularly gravitate to team sports.

He invited Ali, a new pal who would become a lifelong friend, hoping that having “The Greatest” in the ring would attract attention.

Kelly was there when Ali pulled up to the field house with a giant box truck on his tail.

“I said, ‘What is this?’” Kelly told me Thursday. “He was always screwing around with me, playing jokes on me.”

This time, Ali wasn’t pulling any funny business.

The Champ had surprised his Irish buddy — the clout-heavy Democratic power broker that Ali's twin girls still call “Uncle Ed” — with a truckload of new heavy bags, speed bags, head gear and boxing gloves ... so many boxing gloves.

“I asked him, ‘Where did you get all this stuff?’ And he put his finger over his lips, like ‘Keep quiet.’ He didn’t want anyone to know about it,” Kelly said.

“He made me promise not to tell anyone, especially the press, that he bought it all.”

Ali died June 3 after a long battle with Parkinson’s disease. He was 74. A public funeral service will be held Friday in Ali’s hometown of Louisville.

Kelly, 92, decided it was time the truth got out.

“The big thing about that equipment was that he did it on his own. I didn’t ask for his help. He heard conversations about how I didn’t have the equipment, but I promised to get it,” Kelly said. “He knew I didn’t have enough [equipment], so he did it on his own.”

The Champ did it for Chicago kids. He didn't require a thank you.

“Every major boxing event I had, [Ali] was there. He loved to be around the kids. He’d walk into a gym like it was nothing and spend time with kids,” Kelly said.

“We became real close friends. I never asked him for anything — not that he would do anything I’d ask him. That was our friendship. He was a no bull---- guy, a straight guy. He was real. He was really real. And I loved him.”

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