"Unfortunately in Turn 2, I had someone on the inside, and I ran a bit wide," Sainz said.
"By the time I decided to go around the bollard, I went around the bollard with a very, very narrow angle, and I misjudged my entry speed around the bollard and hit the wall pretty heavily.
"A misjudgement by my side, a mistake. I still think that corner shouldn't exist. It's not a very nice corner to drive around, and it generates these kind of situation. But I just misjudged it.
"It's still a corner that is not well designed. You saw today in the race just how many people are missing that apex, and having to go around the bollards, destroying the bollards, it's clearly not a great corner."
Daniel Ricciardo was also hit with a five-second time penalty during the race for failing to follow the bollards, while Haas driver Romain Grosjean destroyed one of them as he passed through the escape route, causing a virtual safety car.