The striker, who is currently Spurs’ only recognised forward as Emmanuel Adebayor is away at the Africa Cup of Nations, limped off in the first half at the Hawthorns.
Gareth Bale’s impressive solo strike gave Tottenham victory against the Baggies and André Villas-Boas confirmed the extent of Defoe’s injury after the game.
“He has some ligament damage to his ankle,” said Villas-Boas.
“We will have to scan it to see if there is further damage and see the full extent of the injury but hopefully it will only be two to three weeks. But we will miss him badly.”
Defoe left the Hawthorns wearing a protective boot and will not feature for England against Brazil in Wednesday’s friendly.
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