For five days, they stood vigil by Mr Lee Kuan Yew's casket, keeping a solemn watch as Singapore mourned.
"It was the one duty we wished we didn't have to do," said Deputy Assistant Commissioner of Police (NS) Lionel Chai, 48, one of the 80 guards who kept vigil at Parliament House last week.
The vigil guards, made up of uniformed officers from the Police, Army, Navy and Air Force, stood in formation - one at each corner of the casket, and a more senior officer at the head of the group, facing inwards.
It is the nation's highest form of respect.
Vigil guards were also deployed at the state funerals of former Cabinet ministers S. Rajaratnam and Goh Keng Swee, as well as at the wake of former president Ong Teng Cheong.
"With our heads bowed, we could not see much, but we could hear people sobbing and, out of the corner of our eye, we could see people kneeling and praying - it was very moving," said DAC Chai.
"You'd feel the grief flow through you, but I reminded myself not to let it affect the dignity of the moment."
Even for these senior officers, it took all of their concentration to keep their composure. Indeed, midway through the interview last Saturday, DAC Chai asked for a minute of privacy. He returned, his eyes red.
Coincidentally, he was also the last vigil commander on Sunday. He stayed behind after his last "watch", to view on television Mr Lee's casket leaving Parliament House for the University Cultural Centre.
There were more than 20 guards in that room, but you could hear a pin drop, he said. "I think all of us realised at that point that Mr Lee was gone," said DAC Chai, who spoke to The Straits Times again on Wednesday.
He talked about how, together with his comrades, they took turns to work round the clock in shifts of 30 minutes each. Enduring numb feet and sore backs, each guard performed about four watches a day.
Twice during each watch, a woman vigil orderly came around and whispered in their ears. "Are you okay? Press on," she would say, telling them how much longer they had left.
She dabbed the sweat from their brows, wiped tears from their cheeks and adjusted their caps or white ceremonial uniforms, if necessary.
"She motivated us," said Superintendent Chan Hee Keong, 41, one of the officers activated to bolster the ranks of vigil guards when the lying-in-state hours were extended to round the clock.
There were only 30 vigil guards initially.
About a decade ago, Supt Chan was one of Mr Lee's security officers, making sure he was safe while he went about his duties from his Oxley Road home to his office at the Istana.
"He was a very disciplined person, and had an intense devotion to Singapore. Even when he was at home, he would still be working," he said.
Another guard, Military Expert 6 Toh Tee Yang, 38, said he would tell his two young children stories of Mr Lee. "I hope to impart the same discipline to them."
Even to the younger officers, Mr Lee was a shining example of leadership, said Deputy Superintendent Sergius Wat, 26. "It is an honour to be able to give our former PM a final farewell."