In the wake of the unexpected death of esteemed comedic actor Robin Williams, Brad Paisley is opening up about how the loss of a great comedian and great human being has affected him.

Paisley, who appeared on the CBS TV show 'The Crazy Ones' with Williams, spoke with the US 99.5 radio show on Thursday (Aug. 14), expressing his sadness at the death of a "brilliant" comedian who "couldn't have been a nicer guy."

"It’s surreal. I don’t understand," the country star admits. "There’s footage somewhere of me playing guitar and [Williams] making up a song in between takes. I was playing a Johnny Cash groove, and he was making up a dirty song that was really funny. I’ll miss him."

Adds Paisley, "Everybody liked him, but obviously he didn’t think as much of himself. That’s really sad that he couldn’t see himself the way we saw him. It’s tragic."

Paisley also tweeted about the actor's death immediately after learning of the news.

“It was so weird. I had all these things planned to tweet that night and was like, ‘I’m not doing anything else,’" says the singer, who has been leaking bits and pieces of his newest album via Twitter over the past few weeks. "I was just so bummed.”

Paisley will release his tenth studio album, 'Moonshine in the Trunk' on August 25.

Watch a Powerful Tribute to Robin Williams