Vettel, starting from fifth, overtook his former Red Bull team-mate into Turn 12 but out-broke himself, and then ran into Ricciardo at the next corner.
The German spun back to 15th place.
“Vettel’s forgotten how to do wheel-to-wheel combat,” said Sky F1’s Martin Brundle as Vettel crashed into a Red Bull for the second race in a row.
“He seems to be on the receiving end of contact every single time he gets into a squabble.
Brundle added: “If anything, it was Vettel giving Ricciardo a bit of a shove”
Hamilton will win the championship if he outscores Vettel by eight points.
How Hamilton can clinch title at US GP
• If Hamilton wins and Vettel is third or lower
• If Hamilton finishes second and Vettel is fifth or lower
• If Hamilton finishes third and Vettel is seventh or lower
• If Hamilton finishes fourth and Vettel is eighth or lower
• If Hamilton finishes fifth and Vettel is ninth or lower
• If Hamilton finishes sixth and Vettel is 11th or lower
More to follow…
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