Is this a joke?
There is literally nothing he could do about that delivery, it was an absolute peach of a ball. No batsman in the world is keeping that out.
Nasser had a good point about Denly though, he does have that habit of planting his front foot. Rob Key played with him long enough to spot it so it's not a new thing by all accounts.
Yes, it was a great delivery, but it wasn't unplayable and Denly has got out to worse balls in the past due to the same technical issue.