Benitez has handed Shelvey a few cameo roles but he had been an unused sub in two of the last three matches - meaning he has been unable to build up any momentum.
When asked about Shelvey, Benitez said: "It's always really difficult when a player is coming on for the last few minutes.
"I think he did really well when he came on against Everton and Bournemouth.
"Against Crystal Palace we conceded a late goal and didn't do well as a team.
"Obviously, in the final minutes we need more experience and manage a bit better.
"Hopefully he will be good for the next games and if we have similar situations we can do better."