In 1992, Bobby Fischer played a series of ten training games with his old friend, the late Yugoslav/Serbian grandmaster Svetozar Gligoric. Gligoric was nearly 70 then, but Fischer clearly felt that Gligoric would make a useful training partner for his forthcoming rematch with Boris Spassky. Fischer won at least three games, Gligoric at least one, and at least two of the games are available to the general public - or at least, two scoresheets are. Whether the attempts to decode Fischer's lousy handwriting are successful is another story!
You can read much more about that training match here, and see the scoresheets for yourself; my attempt to reconstruct those games is here.