(CNN) -- Musician JJ Cale, whose songs "Cocaine" and "After Midnight" were made famous by Eric Clapton, died Friday after suffering a heart attack, the president of his management agency said. His contemporaries considered him a legend, even if many fans weren't familiar with his name. He was 74.

"JJ Cale was loved by fans worldwide for his completely unpretentious and beautiful music," said Mike Kappus, president of the Rosebud Agency. "He was loved even more dearly by all those he came in contact with as the most real and down-to-earth person we all knew."

Lynyrd Skynyrd made Cale's song "Call Me The Breeze" famous, and bands including Santana, The Allman Brothers, Johnny Cash, and many others covered his songs.

He won a Grammy for his 2006 album with Clapton, called The Road to Escondido.

"He was incredibly humble and avoided the spotlight at all costs but will be missed by anyone touched by him directly or indirectly," Kappus said. "Luckily, his music lives on."

The singer-songwriter passed away at Scripps Memorial Hospital in La Jolla, his official website said.

There were no immediate plans for funeral services, it said.

His official biography describes Cale as someone for whom music is all he's ever known.

"I remember when I made my first album, I was 32 or 33 years old and I thought I was way too old then," Cale said, according to his bio. "When I see myself doing this at 70, I go, 'What am I doing, I should be layin' down in a hammock.'"

He was living in Tulsa and had given up on making money in the record business when his career was suddenly made by Clapton's cover of "After Midnight."

That moment changed everything for the musician, his biography states. After Clapton picked up his song, Cale drove to Nashville to record his first album.

Other musicians who covered Cale's work include The Band, Chet Atkins, Freddie King, Maria Muldaur and Captain Beefheart, according to his biography, which also notes he was asked whether it bothered him that fellow musicians considered him a legend while many fans did not even know his name.

"No, it doesn't bother me," Cale said. "What's really nice is when you get a check in the mail."