Bale was absolutely furious, giving a sarcastic clap to Foy and shaking his head in disbelief.
And you can understand why: Sidwell's challenge was ridiculously late, and his outstretched boot went cleanly through Bale's two legs as he ran.
There was only one problem: rather than keep on running and go down naturally, Bale made the ridiculous decision to dive.
He threw his hands back and produced a swallow dive so extravagantly theatrical you'd have thought he was eyeing up a transfer to the Bolshoi rather than Real Madrid.
The perfectly-placed Foy knew, as did everybody else in the stadium, that Sidwell had probably contributed to the Spurs winger coming down. But he'd certainly not done as much to bring Bale to the turf as Bale did himself, giving the ref no choice but to punish the only offence that he knew for sure had been committed: the flagrant dive.
Spurs boss Andre Villas-Boas tried to claim later that Bale is no diver - but frankly, his protestations were no more convincing than his star player's dive.
Bale may well head to Spain in the summer; if Jose Mourinho or Tito Vilanova are watching, they will know that the first thing they have to teach him on the training pitch is how to go down convincingly.