What's a shame is he hit the ball well on all of the shots that went into the water. A little less backspin on them and they're all tight to the pin.
Too much backspin on his shots...so much that the ball "jumps" to the lake when it lands!
A longer club with less swing would have been more effective maybe...
When I first started playing golf in the early sixties, I was fascinated by how the pros could get their ball to land on the green past the pin and then get it to back up 15'-20' or more.
I thought that was really cool, so I wanted to be able to do that as well. Simple physics told me that I needed to catch the lower part of the back of the ball with the club head on the way down, rather than at the bottom of my swing in order to generate that much backspin.
So I learned to do that very well.
However, if you know how to do that, you also know how NOT to do that, which Sergio seemingly forgot today.
You are correct about hitting down on the ball to get back spin. The problem is that to make that shot you must "trap" the ball while hitting down picking it clean without taking a forward divit which is tough if you are attacking the pin. He could have easily went down a club and ran through the green. That is why his ball was hit the same way consecutively, to get in tight. The last shot his hand comes off the club as he attempted to hood the ball slightly to take out height and a little less backspin but the results was basically the same. That is demoralizing to weekend warriors. These pro's shake it right off. Great player and great game none the less.
Hooding the club, getting a lower height might be the most amazing thing ever to create even MORE backspin.
I've learned how to hit low wedges that land on the green with significant forward energy, bounce twice, then totally freeze up and come to a dead stop.
That's a very cool shot and at times, a very useful shot.