We have already seen what happens when non-keepers take over the roles of keepers, as in https://abn397.wordpress.com/2020/11/29/part-time-wicket-keepers-in-tests/
It now remains to see what happens if wicket-keepers become ordinary fielders or bowlers.
Keepers who took catches while deputizing as non-keepers:
We see that Tatenda Taibu is the ONLY Test keeper to take a catch as a non-keeper. He also took one wicket.
Keepers who took wickets while deputizing as non-keepers:
Apart from Taibu, there are several others led by the Hon. A Lyttelton who had figures of 4-19. W Storer took a wicket apiece in two different innings. Kirmani represents India here.
In some cases the bowling captain asks the keeper to bowl out of frustration where no one else can take a wicket, or when the match is ending without any sign of a result.
See Lyttelton’s match here:
While Zimbabwe suffered one of its then-customary heavy defeats, Taibu took Jayasuriya’s wicket and caught Sangakkara as a fielder. Later he returned behind the stumps and caught Samaraweera.