Bale was booked by referee Martin Atkinson for simulation after he appeared to be clipped in the penalty area by Sunderland’s Craig Gardner in the second half at the Stadium of Light.
The caution means that Bale will miss Tottenham’s clash against Reading on New Year’s Day – and Villas-Boas was left distraught by the decision after watching his side come from a goal down to win 2-1.
“It’s a big mistake from the referee,” said Villas-Boas, whose side moved up to third in the Premier League table.
“I understand that reputations are created from the outside – from the media – and it’s a bit unfair.
“If you see the images, Gardner focuses not on the ball but the player. It’s extremely unfair that he misses the Reading game for such a big mistake.
“If I’m not wrong, we had the same situation with Defoe in the first half. It looks like persecution [against Bale].
“Players have a responsibility and we have to take that into consideration. We want to take it out of the game. I think our game is respectful and there is fair play.
“But with the speed they go and then there is contact it is a difficult one for the referee. To see Gareth punished again is a little bit unfair.”
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