The painting on the side of a tall apartment building is expected to be done by Friday Nov. 1, which would have been Valenzuela's 64th birthday. It is also Dia de los Muertos, and possibly will be Game 6 of the Dodgers-Yankees World Series.
It will be a "space for mourning and for healing and for celebration" said artist Robert Vargas, who has painted other large-scale murals throughout the city, including one of Shohei Ohtani in Little Tokyo.
As the Dodgers prepare to face the Yankees in the World Series for the first time since 1981 - when Valenzuela threw a complete game win - fans are mourning the pitching great and Spanish-language broadcaster.
"A piece of me died last night," said Richard Santillan, a retired professor and baseball historian who helped write a book on Spanish baseball broadcasters.
He remembers being at Fernando's first start back in 1981 and also being at Dodger Stadium when Valenzuela threw his only no hitter.
"He left us an extraordinary legacy both as a player and as a human being," he said.