Ben Smith has been ruled out of the Highlanders' two-match tour of South Africa with an ankle injury.

The fullback tweaked his left ankle in the sixth minute of his team's 57-14 win against the Stormers in Dunedin on Friday.

He had the ankle strapped and played on, but by Saturday morning was wearing a moon boot.

Smith will miss his team's matches against the Cheetahs in Bloemfontein and the Bulls in Pretoria, and could rejoin them for the clash against the Force in Perth.

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