The 83-year-old icon Barbra Streisand sang for her friend Redford, delivering a few bars from "The Way We Were" for her co-star in the film of the same name.
"Bob had real backbone, on and off the screen," said Streisand. "I called him an intellectual cowboy who blazed his own trail."
PROMO OPPORTUNITY
The Oscars were broadcast by the network ABC, which is owned by Disney, and organizers took the opportunity to advertise the studio's upcoming films.
While presenting awards, Sigourney Weaver and Pedro Pascal -- stars of this year's "Star Wars" film "The Mandalorian & Grogu" -- performed a bit that featured Grogu (also known as Baby Yoda) in the audience.
And Vogue doyenne Anna Wintour alongside Oscar winner Anne Hathaway delivered a humorous sketch that doubled as promo for the forthcoming "The Devil Wears Prada 2," to be released this spring.
Marvel cinematic universe stars Chris Evans and Robert Downey Jr. also reunited onstage ahead of the release of "Avengers: Doomsday" later this year.
CONAN'S JOKES
Host Conan O'Brien nodded to politics and pulled a few punches, some with global appeal and a few one-liners for the insiders.
"It's great to be back hosting the Oscars. Last year, when I hosted, Los Angeles was on fire. But this year, everything's going great," he joked, pausing for effect.
O'Brien also had a pointed industry remark for Netflix CEO Ted Sarandos: "It's his first time in a theater."