Perez was forced to retire early after pulling over on a straight with an oil leak with his car, meaning he didn't finish the demanding race and his team-mate could only manage a P13 finish.
Lance Stroll was consistently in the mix to get a points finish, but the Canadian driver couldn't turn his solid drive into anything worthy of points for Racing Point, who overall had a disappointing weekend in Singapore.
"I'm very disappointed," Perez said. "It was a very demanding race, but it was a race that was coming to us. We were there and we were very patient, keeping out of trouble, which is priority number one here."
Perez believes without the issue to his car then he could have easily found himself inside the top 10 when reaching the chequered flag.
"We were looking very good all the way to the end and on course for some points. Unfortunately, we had an oil leak and the team told me to retire the car. It's a big shame because I feel like points were possible today."