I always felt that Lord's was India's big game in this five-match series.
They won here on the last tour in 2014 but arrived this time trailing 1-0 and with Trent Bridge, where England are so strong, around the corner.
India had to win here because, as we've seen when England have been away from home, when you get on a downward slope, it's very hard to turn that around.
Essentially, they lost the match on the first day, and England are now in a really strong position for the rest of the five-match series.
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India were ambushed. England were all over them - James Anderson in the first innings, then he and Stuart Broad in the second as India were beaten by an innings and 159 runs.
Broad was superb. I thought he looked mean: it was not pleasant, facing him out there on a pitch that was going up and down, with his height and his speeds up at 88mph.
I said to him after the match that he owes me a very nice case of something after he had India captain Virat Kohli caught at short leg.
We spoke at Edgbaston about Kohli, and I said he should have a short leg in place early in Kohli's innings. He asked why. I told him the reasons, and now I'll be awaiting my return!
He didn't have much rhythm from the Nursery End in India's second innings. His four-over spell from there was tidy enough, costing just nine runs, but when he switched ends, it clicked.
Before tea, he took 7-4-7-4 from the Pavilion End. From there, he had the breeze behind him, which pushed his speeds up, and he ran in harder, with more intent.
On the first day, it was a 'pitch it up and let the ball swing around' sort of situation, and that's what he was trying to do, and bowl a fuller length.
But on the final day, he really preyed on the batsmen's mind. He rapped Ravichandran Ashwin and Hardik Pandya on the fingers, and looked as if he was full of rhythm.
That can happen sometimes, if you just run in and let the ball go as fast as you can. Rhythm is a very elusive thing, but as a bowler, you know when you've found it, and he did just that at Lord's.
'No-one had any idea why Root didn't declare'
There was a lot of talk about whether England should have declared in the morning, and put India in to bat straight away, rather than batting on to 396-7 before declaring.
No-one I spoke to, be they English or Indian, has got any idea why Joe Root did not declare. In a dressing room it can be blinkered, and you stick to the plans that you have and so on - but up where we are, you're just watching a game of cricket.
I would imagine that England would keep the same side for Trent Bridge. Chris Woakes played a match-winning innings with the bat, and I'd expect conditions to be fairly similar.
'India have no time to play anyone into form'
In contrast, I think that on reflection, India would feel they picked the wrong side. They are a team short of preparation. One red-ball match that lasts three days is not enough.
The conditions were extreme here, particularly on the first day of play, but if you haven't prepared yourself then the odds are that you are going to lose.
They do not have a game between now and the third Test starting on Saturday, so there is no time to play anyone into form to give them some options.
Virat Kohli's sore back is also a huge worry, although he has said that he believes he will be ready for the next Test. You don't want India to be without him. He's one of the big characters of the series, and you want him to play.
Ultimately, though, India were not at their best. For the number one team in the world, it is disappointing.
Jonathan Agnew was speaking to BBC Sport's Amy Lofthouse.