The Australian, who started the wet-dry race on the Principality's fabled streets from pole, was absolutely livid at having been beaten by world champion Lewis Hamilton.
"It hurts. I'm not sure where to go from here, what to do," the normally-chirpy and grinning Red Bull driver said.
This time, it was a bungled pitstop - which saw him waiting stationary for a set of tyres - that cost him the win.
Ricciardo says he was "screwed" by the team both times.
"It's two weekends in a row I've been screwed now," he said. "Two races in a row, two races in a row. That's all I can say.
Indeed, on the radio after the chequered flag, Ricciardo had growled: "Nothing you can say can make it any better. Just save it."
For the record, team boss Christian Horner said it was a miscommunication based on the fact that the pitwall at Monza is actually upstairs above the garage.
Dr Helmut Marko called it a "human mistake", and apologised.
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