The Scotland international kicked out at Spurs defender Emerson Royal at the Tottenham Hotspur stadium.
Robertson was shown a straight red card by referee Paul Tierney as a result.
Warnock implied that the 27-year-old should not have been sent off due to the lack of force behind his tackle. All we will say is that we don't agree with the aforementioned take.
The reality is, Robertson's tackle was clumsy and reckless. Royal could have been seriously injured.
Therefore, Robertson deserved to be sent off. The Premier League fixture ended in a 2-2 draw.
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