Singh's overall score was 2-under 282.
"The last hole, I'm happy the way it finished," said Singh.
After his 30th career second place finish at a European Tour event, Harrington (69) eased past England's Paul Casey to win the Order of Merit title as the European Tour's leading money winner.
"It's very hard when you can't do anything about it," Harrington admitted after sitting for more than an hour in the clubhouse, waiting for the finish. "I never like watching golf that I'm involved in because I don't like wishing people bad. You don't want to watch people make birdies either."
Celebrity Couples of 2014 [PHOTOS]