That's Al Kooper of Blood Sweat & Tears fame on keyboards. Kooper played on this track and "You Belong To Me" at a session at George Harrison's home in England. Kooper relates in his memoir Backstage Passes and Backstabbing Bastards
that he was a little surprised to be invited to play with two former Beatles. A mutual friend, Herbie Flowers (bass and guitar player for Elton John, David Bowie, and others), hooked them up. Kooper thought it was Flowers playing a prank on him when the call came in at 9:30PM the night before the session, but it was George Harrison asking what kind of keyboard instrument Kooper preferred - from his choice of a Hammond B3 organ, a Fender Rhodes, a Wurlitzer piano, and an Arp Omni.