At the invitation of George Harrison, Russell played piano on Badfinger's third album, "Straight Up" in the summer of 1971. The piano part complemented Pete Ham's and George Harrison's dual slide guitars on Badfinger's "Day After Day". The "Straight Up" sessions were interrupted when many of the musicians left for New York City to participate in The Concert for Bangladesh, at which Russell performed a medley of the songs "Jumpin' Jack Flash" and "Young Blood" and sang a verse on Harrison's "Beware of Darkness". Leon performed piano, vocals, bass and backing vocals at the Concert on 1 August 1971. "The Concert for Bangladesh" album released in 1971 was a major critical and commercial success. The album topped albums charts in several countries and went on to win the Grammy Award for Album of the Year in March 1973. The Concert also became an Apple concert film directed by Saul Swimmer.