Mac Miller's manager is still having a tough time coming to terms with the rapper's tragic death, insisting his loss is "so surreal".

The Self Care hitmaker, real name Malcolm McCormick, suffered a fatal drug overdose in September (18), and hearing the news was like a "punch in the gut" for his longtime representative Christian Clancy, because there were no signs to suggest the 26 year old had been struggling mentally or physically.

Clancy recalls the last time he saw Mac, just two days before his death, and reveals the star appeared to be in great spirits as he focused on his health.

"I last saw him two days before he died," Clancy writes in an op-ed for The Guardian. "He was very open about his struggles throughout his career, but he had been fully focused and engaged. He knew the progress he had made, battling his internal dialogue - it wasn't easy, but he was doing it and feeling the rewards.

"A few days before, he was sending Kelly (Clancy's wife) and me workout videos of himself alongside Rocky-themed music. He was happy and in as good a mental state as he had been since we'd known him."

It's for that reason that Miller's loss has been hard to accept, despite having had some time to nurse his heartache.

"That's why all of this is so surreal - it was like a punch in the gut," Clancy continues. "There was so much in front of him that he was excited about. He was about to go on tour... He knew he was at his best... and couldn't wait to show his fans who he now was and the direction he was fully leaning into."

Looking back on Miller's legacy, Clancy hopes fans will learn from the way Mac carried himself, treating others just as he would want to be treated himself.

"He was a spark to so many people," he concludes. "In a world dominated by ego, he led with the soul and lived by focusing on similarities rather than differences - that's a lesson we all could use. I truly miss you, Malcolm."