There are 7 days in a week, so Tony made 1 * 7 = <<1*7=7>>7 sandwiches.
On Saturday, he made 1 extra sandwich, so he made 7 + 1 = <<7+1=8>>8 sandwiches this week.
A sandwich has 2 slices of bread, so he used 8 * 2 = <<8*2=16>>16 slices.
Thus, Tony has 22 - 16 = <<22-16=6>>6 slices of bread left.
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