Second-half goals from Winston Reid, Ricardo Vaz Te and a superb solo effort from Ravel Morrison sealed an impressive away win for the Hammers and condemned the north Londoners to their second league loss of the season.
The result left Tottenham in sixth place in the Premier League table, three points behind leaders Arsenal.
And Townsend was in no mood to make excuses for the humiliating defeat after the match.
“We went into the game looking for the three points, we didn’t take our chances and we paid for it. That’s football,” said Townsend.
“We’re not going to make excuses, we weren’t good enough on the day.
“We’ve two weeks off now, so we’ll regroup and look to come back strong against Villa.”
Tottenham’s next Premier League match is a trip to Aston Villa on 20 October.
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