Liverpool captain Jordan Henderson says striker Daniel Sturridge gives the Reds a "fear factor".
Sturridge, 26, scored on his first Premier League start since October in Sunday's 6-0 win over Aston Villa.
It was only his sixth league appearance of a season interrupted by knee, foot and hamstring injuries.
"Any centre-half in the world would be worried coming up against him," said Henderson. "They know how quick he is, how sharp he is with the ball."
It has been reported that Sturridge, who has scored five goals in eight games in all competitions this term, wants to leave Anfield at the end of the season over criticism of his injury record.
"A lot gets said about him outside of our group," said midfielder Henderson.
"I know it hurts him and I know it is hard for him to take. He is doing things to try and get back.
"I have been with him a lot while he has been out. He doesn't want to be injured. He is more annoyed than anyone that he isn't playing.
"But now he is back, he has got a smile on his face and he has been world class."