Nadal was leading 7-6, 6-6 and 3-2 up in the tiebreak when showers halted play on Thursday and with Friday's proceedings completely washed out, the Spanish third seed was in no mood to hang around.
He won four successive points to wrap up the tiebreak 7-2 and from then on Gonzalez's game simply fell apart, allowing Nadal to wrap up the win which took over 40 hours to complete thanks to the bad weather.
Nadal, whose victory allowed him to reclaim the world number two ranking from Andy Murray, will next face Argentine Juan Martin del Potro for a place in his first final at Flushing Meadows.
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