Post Malone Honors Mac Miller in a Big Way Onstage

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Malone and Miller had been open about their plans to collaborate together on an album.

Post Malone is coping with Mac Miller's death the best way he knows how. 

The "Rockstar" rapper took the stage at the KAABOO Del Mar festival in San Diego on Friday wearing a customized white T-shirt with the words, "RIP Mac Miller," front and center. Colorful rose buds were scattered over the rest of the shirt, which Malone paired with heart-printed white pants and white sneakers. 

The 23-year-old rapper took to Instagram to share a snap of his shirt, but left his caption blank. Miller and Malone were friends, and were even going to collaborate on an album together before Miller was found dead of an apparent overdose on Sept. 7. 

In an August interview with Rolling Stone, Miller opened up about jamming out with Malone. "Me and Post have been talking about doing an album,” he said. “So we got together. And then Frank Dukes has worked on a bunch of my records, but we had never met, so he came through too. And then Thundercat appeared and we all started jamming.” 

"It was beautiful,” the late rapper recalled. “We were just having a great time.”

Malone was one of the many stars to react to Miller's death on social media last week. "God f**king dammit," he tweeted at the time. "You were such an incredible person. You changed so many lives. Had so much love in your heart. You inspired me throughout highschool, and I wouldn't be where I was today without you. Never a more kind and sincere and beautiful person. I f**king love you mac."

See more on Miller in the video below.