"Both Max, myself and other team members received a huge number of messages about the incident," Horner wrote in his Red Bull column.
"Copse is an incredibly high-speed corner, one of the biggest corners on the F1 calendar as any driver will tell you, and one to be respected.
"When you look at the incident closely, Max took a wider line into Copse compared to Leclerc when Hamilton overtook him in the race. Hamilton braked late and overshot the corner.
"He was travelling at such a speed that he was never going to make the apex of the corner and his trajectory through Copse meant he was never going to miss Max, even with braking he ran very wide after the accident.
"Had Max made it through Copse, I don't think Hamilton would have seen him again that afternoon as he learned in the previous day’s Sprint Race.
On Hamilton's actions, Horner added: "No matter how experienced or talented, all drivers experience a build-up of pressure at times and this was a moment of extreme pressure for Hamilton in the championship, becoming the hunter as opposed to the hunted, and in front of his home crowd who saw him defeated the previous day at a track that has always been a Mercedes stronghold.
"We all know that these situations can bring out a different driving style and one that is not characteristic of a world champion, but it is at these times that we see the increased risk."
Verstappen "more motivated" ahead of Hungary
Verstappen was hospitalised after the 51g impact but released on the same night as the race.
Horner believes his driver will be motivated by the incident and that there are positives to take despite the team failing to score at Silverstone.
"For Max, despite being battered and bruised, he will be more motivated on-track and the positives we can take from the weekend are that last year, we qualified a second off Mercedes.
"This year, we were within a tenth. We had a faster race car and we were able to beat them in the sprint race which shows that the team’s monumental effort with the support of Honda, has allowed us to close the gap to the seven-time world champions and the pressure is on them."
What do you think?
Wow this is turning into a pantomime now.
Karen Horner and his ilk really wants to ride out this wave. Get over it, it's done, we're tired of this. Go and rub some lotion on your "battered and bruised" golden boy and pour his dad another drink.
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