Mignolet, signed for B£9million from Sunderland last summer, impressed early in the season but Rodgers acknowledges he now needs a lift.
Rodgers said: "Confidence-wise it is important for me to lift all the players.
"And for Simon, it is something I will reinforce with him.
"He is still an outstanding goalkeeper but when you make those mistakes they get highlighted more as a keeper.
"But he has come here because he's an outstanding goalkeeper and, I repeat, you don't lose your talent.
"Players will succeed if they have confidence and part of my job is to help deliver that confidence to them."
Mignolet, 25, could be rested this weekend as Liverpool travel to Bournemouth in the FA Cup fourth round.
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