North led 7 against 3, and declarer made ten fairly routine tricks. But it could have been held to nine - south must take A and switch to Q, later getting a spade ruff.
I don't think I would have found this defence, but it does look possible. North is quite likely to have K and A - this declarer would have opened any 11-count. The play is likely to cost a spade trick only if North has 10xx or perhaps three small in the suit.