Sylvester Stallone says it was a "privilege to know" Muhammad Ali.
The 69-year-old actor has paid tribute to the late boxer - who was his inspiration for Carl Weathers' Rocky character Apollo Creed - by sharing a number of old pictures of himself with the sporting legend on Instagram.
Alongside a video of them presenting together at the 1977 Oscars, he wrote: "Fantastic man who I came to know well.... He was the real Apollo Creed"
Another picture was simply captioned: "Another flashback in time", while a third read: "The real Apollo Creed meets the movie "Apollo Creed" RIP (sic)"
The Expendables star completed his trip down memory lane with a picture of his first meeting with Ali, who died on Friday from septic shock aged 74.
He wrote alongside the black and white image: "And finally our first meeting where the champ gave me a slight tap in the stomach... And amazing humanitarian. A privilege to know him!!"
Meanwhile, wrestler-turned-actor Dwayne The Rock Johnson has also paid a heartfelt tribute to Ali for being a constant source of inspiration to him.
He shared: "I was in the air last night flying from Atlanta to London when I got the text from a close friend that within' a few hours we were going to lose Muhammad.
"Ali inspired myself and generations around the world to be hungry to achieve, work as hard as you possibly can, to be a great as you possibly can be and make sure that not a day goes by where you don't do your absolute best to make the world smile and feel good. Feel inspired. And feel that no matter how hard times may be, there's always hope for tomorrow.
"From hanging out with you in New Zealand as this little punk kid, to years later as a WWE rookie when you whispered to me "Can you rumble?" to a few years later when you bestowed upon me The People's Champ moniker. I will always be grateful for the impact you've had on me. Thank you and I'll miss you.
"Much love and strength to the Ali family. Rest in love and light Champ. You'll always be the Greatest of All Time. And pretty.(sic)"
- Bang! Showbiz