Mercedes' Lewis Hamilton was on provisional pole after his initial flying lap in the final round of qualifying for the United States Grand Prix. However, he was certain that he would have to go even faster if he wanted to hold on to it.
“That was close," Hamilton said after the end of Saturday's session. "I didn’t know how close it was going to be once we got to qualifying.
"Obviously once we got to that last run I knew it was quite edgy between us and it was going to require a solid lap.
"The first one was decent but not good enough," he added. "The second one was just that little bit better that enabled me to pull that out."
“I've had some races where I have not actually done a better time," he acknowledged. "I have had to bail out the second lap.
"I was very adamant that I was going to do a better second lap [this time], so I am very happy with that."
Hamilton's first run was indeed beaten by Kimi Raikkonen, and then by the Finn's Ferrari team mate Sebastian Vettel. But Hamilton's second effort of 1:32.237s was a significant improvement, and he ended up 0.061s quicker than his title rival.
Hamilton and his team mate Valtteri Bottas had been quick in wet practice on Friday, but had appeared to lose ground in dry conditions on Saturday.
“It started out very, very green and very slippery in practice 3,” Hamilton explained. "Then once we got into qualifying it was just rubbering in so it was getting faster and faster every session.
"The wind direction is a beautiful headwind going into the Esses, so the Esses is just incredible," he added. "It is a little bit like Maggotts and Becketts and there is such a big crowd here [supporting us]."
The outcome of qualifying means that Hamilton starts tomorrow's race from pole position for the 72nd time in his Formula 1 career.
Vettel meanwhile will line up in fifth place on the grid tomorrow due to a penalty he received for speeding under a red flag in first practice on Friday.
It's a body blow to the German who is making his last stand to prevent Hamilton winning a fifth world championship: if Hamilton wins Sunday's race, Vettel must finish in second place.
But thoughts of clinching the title this weekend are far from Hamilton's mind - or so the driver says.
“I just hope for better weather for everybody that is in the grandstand and I hope that it is an exciting race tomorrow.
"We did a fan signing earlier and I have never seen the fans so hyped before so it was great," he added. "A big thank you to the team and everyone here."
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