Gone was the rough, tough-talking, vulgar personality that voters had seen in stump speeches and campaign rallies.
Now, he was an emotional son, seeking blessings from his parents for a monumental task ahead.
He had come a long way from being the problem child who had often got into trouble and who was kicked out of school.
“Help me Mom,” he said in the local Bisaya dialect as he sobbed quietly in front of his parents’ tomb.
“I’m just a nobody.”
The display of emotion, caught on video and photos and posted on Facebook, showed a starkly different man from the Mr Duterte that critics have dubbed a “butcher” for advocating the murder of drug traffickers and other criminals.
A former lawyer and prosecutor, Mr Duterte has been the mayor of Davao city for 22 years.
Monday’s presidential election was his first foray into national politics.
His campaign manager says the brash image, the obscene jokes, the outlandish promises that became the Duterte persona were a strategy to attract voters.
“That’s part of the game. You know, in Philippine elections you have to act like a comic, you have to find ways for you be in the headlines,” said Peter Lavina, Duterte’s spokesman, speech writer and campaign manager.
“The jester, the jokes. That’s part of the game.”
If it was a game, the crowds played along, despite the risque jokes.
One of his most controversial statements was about an Australian missionary who was gang-raped and killed by inmates in a 1989 jail riot.
“I was angry, because she was raped, that’s one thing. But she was so beautiful, the mayor should have been first, what a waste,” he said.
When Australian diplomats protested, he told them to “shut up.”
He has referred to both outgoing president Benigno Aquino III and Pope Francis as a “son of whore”, a popular Philippine insult.
“Well, that is his style in Davao, in every election,” said Mr Lavina.
“That’s why he can capture the crowd for two to three hours, because he has this penchant for storytelling, cracking jokes and even laughing at his own self.”
However, one thing he was not joking about, Mr Lavina said, was his promise to eliminate crime, one of the three “evils,” along with corruption and poverty, that the Southeast Asian nation is battling.
Mr Duterte has promised to “butcher” all criminal suspects, including drug lords, and dump their bodies into Manila Bay to fatten the fish.
He does not deny that, as mayor, he has ordered extrajudicial killings of suspected criminals.