Sainz started 15th after a crash in qualifying and navigated the turn one chaos to find himself in the top order.
Before learning of Vettel's retirement, Sainz said: "I thought it [a podium] was on the cards.
"But I don't know what happened in the first pit stop when we pitted for slicks. Sadly, the AlphaTauri and the Williams went in front of me when I was in front of them at the pit stop and that meant the whole of the first stint I was behind them.
"Once they got out of the way, I managed to overcut them and show very, very strong pace and then Lewis played the trick he has played here the last few years with the pit stop and passing everyone at the end.
"I tried my best. I had to fuel-save a lot in the last 10 laps. The McLaren in front in the last corner, he could have got out of the way quite clearly earlier than that but it is what it is in the end."
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