The Cornishman even won a standing ovation from United's sporting fans at the final whistle.
Two of English football's most talented teenagers, Wayne Rooney and James Milner, traded goals and only Martyn's brilliance prevented The Whites third successive win.
Leeds were so short of midfielders that they had specialist central defenders Dominic Matteo and Lucas Radebe in the engine room. It was Radebe's first appearance since December 22 and it came the day after his 35th birthday.
Rooney had already forced Paul Robinson into a swooping save before the 18-year-old Everton marksman pounced for a 12th minute opener.
Leeds failed to clear a corner and when the ball ran to him just outside the penalty box, Rooney clinically drove a low shot into the bottom left corner for his ninth goal of the season and his fifth in six games.
Rooney almost scored again three minutes later but couldn't quite supply the finish at the foot of a post with Leeds' defence sliced wide open.
Martyn nearly presented his former team-mates with a soft equaliser on the half hour. Making a hash of a clearance, he sent the ball straight to Milner on the left.
With Martyn out of position, Milner quickly shot towards goal but the keeper raced back to make a miraculous one-handed save at full stretch.
Martyn did his former team no favours as he pulled off two more superb saves to deny Alan Smith, prompting Leeds fans to chant "Nigel, Nigel give us a goal."
When the equaliser did arrive in the 49th minute there was nothing Martyn could do about it. Smith and Viduka combined to present Milner with a shooting chance from inside the D and the 17-year-old's powerful left-foot drive flew just inside the left upright.
As Leeds desperately sought a winner, Thomas Gravesen almost deflected Jermaine Pennant's free-kick into his own net and Martyn made yet another breathtaking save from Smith, who couldn't believe his misfortune.