Paul McCartney Pens Emotional Tribute to Sir George Martin: 'He Was Like a Second Father to Me'

The Beatles lost one of their own on Tuesday when acclaimed music producer Sir George Martin, who was helmed as "the fifth Beatle," died at age 90.

Martin has been attributed with helping The Beatles gain worldwide success, and the members of the band couldn't agree more.

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Early Wednesday morning, Paul McCartney posted a tribute on Facebook to his longtime friend and music colleague, explaining how much Martin meant to him. "I’m so sad to hear the news of the passing of dear George Martin. I have so many wonderful memories of this great man that will be with me forever," the 73-year-old musician wrote. "He was a true gentleman and like a second father to me."

Continuing his emotional message, McCartney looked back on one of his favorite memories when Martin suggested the band bring in a string quartet to record "Yesterday" with them. "I said, 'Oh no George, we are a rock and roll band and I don’t think it’s a good idea,'" he recalled telling the music producer. "With the gentle bedside manner of a great producer he said to me, 'Let us try it and if it doesn’t work we won’t use it and we’ll go with your solo version.' I agreed to this and went round to his house the next day to work on the arrangement."

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He added, "When we recorded the string quartet at Abbey Road, it was so thrilling to know his idea was so correct that I went round telling people about it for weeks. His idea obviously worked because the song subsequently became one of the most recorded songs ever with versions by Frank Sinatra, Elvis Presley, Ray Charles, Marvin Gaye and thousands more."

The two went on to collaborate on arrangements of "Eleanor Rigby," "Live and Let Die" and "many other songs" that McCartney wrote.

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"If anyone earned the title of the fifth Beatle it was George," McCartney touted. "From the day that he gave The Beatles our first recording contract, to the last time I saw him, he was the most generous, intelligent and musical person I’ve ever had the pleasure to know."

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Other members of the Beatles family also paid tribute to Martin. Ringo Starr seemingly broke the news of the producer's death when he tweeted: "God bless George Martin peace and love to Judy and his family love Ringo and Barbara George will be missed."

John Lennon and Yoko Ono's son, Sean Ono Lennon, posted a pic of Martin, with the message: "R.I.P. George Martin. I'm so gutted I don't have many words. Thinking of Judy and Giles and family. Love Always, Sean."

"I am proud to have known such a fine gentleman with such a keen sense of humor, who had the ability to poke fun at himself," McCartney continued in his post. "God bless you George and all who sail in you!"