The triple world champion won by more than 30 seconds at the Marina Bay, but Horner told Autosport that he is not expecting a similar display.
He said: "There were times last weekend when Sebastian was two seconds quicker than the rest of the field, but I think it was due to unique circumstances.
"It was a circuit he was completely on top of and the setup of the car was working well. It was man and machine working at the top of their game."
The German currently leads the drivers' standings by 60 points.