Austin - Sebastian Vettel said he felt mixed emotions after keeping his slender title challenge alive by finishing fourth in Sunday's United States Grand Prix, won by Ferrari team-mate Kimi Raikkonen.
The four-time champion, who started fifth on the grid after taking a three-place penalty, recovered from an opening lap spin to fight through the field in a tactical contest that left Lewis Hamilton frustrated in his bid to clinch his fifth drivers world title.
"My feelings? Mixed," he said. "Happy. Really happy for Kimi. But not much for me. It should have been a better day."
Vettel can only stop Hamilton taking his fifth drivers title next weekend in Mexico by winning the race and hoping Hamilton hits problems that keep him out of the top seven places.
He said he suffered a major blow when he clashed with Red Bull's Daniel Ricciardo on the opening lap.
"I must have been in his blind spot. I'm not sure he saw me. The corner kept tightening and we hit. It was a big loss for me."
Vettel's disappointment took nothing away from a resurgent Ferrari's satisfaction in recovering their mid-season pace, after abandoning several recent upgrades, and claiming a revitalising victory.
"I am very proud of them all," said Ferrari team chief Maurizio Arrivabene.
"I was always proud of the guys and even more when we are winning races. It's been hard for us recently and we had a race engineer pass away last weekend.... I have nothing more to add. It was great today. Thank you USA!"
Mercedes team chief Toto Wolff admitted that Ferrari had been faster than his team, as he had feared.
"We lacked the pace and I said don't close it too early. They are very fast. Kimi winning is great for him and for Ferrari, so let's go to the next race in Mexico now.
"It was difficult to overtake, but for us it was a strategy that got worse as it progressed. We need to re-think and see what we can do better. We put on a good show altogether and that's what's more important."