Liverpool manager Arne Slot says he "can't accept" striker Darwin Nunez's work-rate in his past two games.
The Uruguay international was a second-half substitute in the win over Wolves on 16 February and the draw at Aston Villa on 19 February, when he missed an open goal.
Nunez did not come off the bench in Sunday's 2-0 win at Manchester City, which took Liverpool 11 points clear at the top of the Premier League.
Slot defended Nunez after his miss against Villa but said he allowed his "disappointment" to impact his work-rate.
"I helped him by saying you can miss a chance," Slot said in his news conference before Wednesday's visit of Newcastle.