The When Harry Met Sally star, who has hosted the Oscars eight times, emerged as the popular choice to replace Murphy hours after the Dreamgirls star announced his resignation on Wednesday (09Nov11).
And it has taken new producer Brian Grazer just 24 hours to sign Crystal up for his first Academy Awards hosting gig since 2003.
In a tweet on Thursday (10Nov11), Crystal joked, "Am doing the Oscars so the young woman in the pharmacy will stop asking my name when I pick up my prescriptions. Looking forward to the show."
The funnyman was expected to be named the host of the 84th Oscars after making an appearance on the 2011 telecast to present a tribute to Bob Hope.
And earlier this year (11), Crystal told reporters he felt "itchy" after his Academy Awards cameo - and he would be prepared to consider a return to the Oscars stage as host.
He said, "It's always fun. It's really hard, but maybe one or two more times... They know where I am."
Officially announcing the news on Thursday afternoon (10Nov11) in Los Angeles, the City Slickers star said, "Some of the best moments of my career have happened on the Oscar stage. I am thrilled to be back there."
Academy of Motion Picture Arts and Sciences president Tom Sherak is thrilled to welcome Crystal back to the Oscars: "He's a comic legend and Oscar icon, and it feels good to have him back where he belongs."
Grazer, who replaced Brett Ratner as the co-producer of the Academy Awards on Wednesday (09Nov11), adds, "Like so many others, I've been eager to see Billy host again."
The Oscars will take place on 26 February (12).