James Haskell says Eddie Jones has made it clear England's players have to perform to a high standard, otherwise they will be replaced in the squad.
Jones has said ahead of England's Six Nations clash with France in Paris on Saturday that nobody is indispensable.
England lost their last match 25-13 to Scotland to damage their hopes of winning a third successive Six Nations title and Jones said he was considering changes to his side.
When asked about the head coach saying no-one was indispensable, Haskell - who has not played for England in nearly a year - joked: "I know that more than anybody else!
"That's the thing that was made very clear by Eddie early on. He will be very honest and give you every opportunity to perform, but if you don't cut it, there's someone else to fill your space.
"He has people in here all the time getting tastes of international training. You just have to perform - if you don't, his coaching staff will move you on."
Despite not playing since last year's Six Nations defeat to Ireland, Haskell is back in the England squad as Jones considers his options ahead of their trip to Paris.
"Being back in the squad has been great," Haskell said. "When you're out and not sure you're going to get back in, to be involved and work with the excellent coaches we've got here has been fantastic.
"If I change from morale booster to actually being involved in the team it will be great!"