Tommy Newsom, the former backup bandleader on "The Tonight Show" whose "Mr. Excitement" nickname was a running joke for Johnny Carson, has...

PORTSMOUTH, Va. — Tommy Newsom, the former backup bandleader on “The Tonight Show” whose “Mr. Excitement” nickname was a running joke for Johnny Carson, has died. He was 78.

Mr. Newsom died of bladder and liver cancer Saturday at his home in Portsmouth, the city of his birth, said his nephew, Jim Newsom.

Mr. Newsom, who played saxophone, joined “The Tonight Show” in 1962 and rose from band member to assistant music director. He retired along with Carson in 1992.

Mr. Newsom won music direction Emmys for “Night of 100 Stars” in 1982 and “The 40th Annual Tony Awards Show” in 1986. “The Tonight Show” received five Emmy awards during Mr. Newsom’s years on it.

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“I hope he will be remembered as a gifted musician,” Jim Newsom said Monday. “I’m sure he will be remembered for his wit and deadpan humor on ‘The Tonight Show.’ And to some of us a certain age, he will always be remembered as Mr. Excitement.”

That was the name Carson gave Mr. Newsom to make light of his low-key personality and drab brown and blue suits — a sharp contrast to the flashy style of bandleader Doc Severinsen.

“As a child, one time Tommy got lost and his parents couldn’t describe him to the police,” Carson once said.

Periodically, Mr. Newsom topped Carson’s one-liners.

When Carson asked him why he kept his jacket buttoned, Mr. Newsom replied that his rear end would otherwise fall off. This prompted executive producer Fred De Cordova to remind Mr. Newsom that the host was supposed to get the bigger laughs.

Along with his work on “The Tonight Show,” Mr. Newsom arranged and composed music for Skitch Henderson, Woody Herman, Kenny Rogers, John Denver and other performers.

He also released several albums as a bandleader, including “Live From Beautiful Downtown Burbank” in 1978 and “I Remember You, Johnny” in 1996.

Survivors include his wife of 49 years, Pat Hernansky Newsom of Portsmouth, and a daughter, Candace Liebmann of Teaneck, N.J. A son, Mark Newsom, died in 2003.