Sergio Perez said he was happy to leave the United States Grand Prix with 10 points after continuing his recent good form by finishing in fifth position.
Perez switched to the Prime tyres when conditions dried and preserved his rubber throughout the remainder of the race, passing Jenson Button en-route to fifth place.
"We are happy to come away with fifth place and ten points from a weekend with such difficult weather conditions," said Perez.
"The track was very damp to begin with and I was lacking pace on the intermediates – sliding around with a lot of degradation.
"Then, when we switched to the softs and eventually the mediums, it was not easy to get the temperature in the tyres and I struggled for grip with each restart."
Perez added that his increasingly worn tyres prevented him from overhauling Toro Rosso's Max Verstappen for fourth.
"There was so much happening in the race and you really had to concentrate because it was very easy to make a mistake," he explained.
"In the final few laps I was getting close to Max, who was struggling on the soft tyres, but there was not enough time to catch him. Overall I’m very happy for the team because we’ve done a really good job this weekend."