The legendary rock guitarist died suddenly on Tuesday after contracting bacterial meningitis.
A source tells ET the Pirates of the Caribbean star is "devastated and still processing the news and mourning the loss of his close friend and collaborator Jeff Beck." The source adds that "Depp and Beck had an extremely close friendship and became closer touring together."
What's more, the source says "Beck's illness came on quickly and took a turn over the last couple of weeks" and Depp "had visited him prior to his passing."
Following a sweeping victory in the defamation trial against his ex-wife, Amber Heard, the 59-year-old actor was seen taking the stage alongside Beck in the U.K. at the Sage venue in Gateshead, in Northern England. It was the actor's first public appearance since a jury ruled in his favor.
While Depp did not mention the trial or the verdict, Beck appeared to, stating, "What a result," the BBC reported at the time.
On that same night, Beck announced that he and Depp had been collaborating on a new album, which was released the following month.
"I met this guy five years ago and we've never stopped laughing since," Beck declared during the concert back in June. "We actually made an album. I don't know how it happened. It will be out in July."
Depp had also appeared with Beck prior to the jury delivering its verdict. Beck's family released a statement announcing the guitarist's sudden death.
"On behalf of his family, it is with deep and profound sadness that we share the news of Jeff Beck’s passing. After suddenly contracting bacterial meningitis, he peacefully passed away yesterday. His family ask for privacy while they process this tremendous loss," the statement, shared across Beck's verified social media accounts, read.
Beck was a two-time Rock & Roll Hall of Fame inductee. He was inducted as a member of the Yardbirds in 1992 and as a solo artist in 2009. He was also an eight-time GRAMMY winner.