The 21-year-old winger is set to face his old team-mates for the second time since joining Manchester City for £49 million last summer. He left in unceremonious fashion after refusing to sign a contract - even if Liverpool paid him £1 million per week, he said - and failed to report for training.
The fractious nature of his departure irked a section of Reds fans, who are expected to avenge their club's honour in the only way a group of supporters can under these circumstances: by booing.
However, the Chilean is certain that Sterling will focus on posting a good performance and block out any howls of discontent that come his way.
"I hope he will be focused just on having a good performance and not thinking about the boos or what happened in the past," Pellegrini told a press conference, as quoted by the Daily Mail.
"For every player it is never comfortable to play against an old team. Everyone has links, friends inside the club. But he is a professional player. He came here to win titles. I don’t think he has anything to prove."
Sterling has scored 10 goals in all competitions and set up another eight this season.
However, he also incurred the wrath of Sky Blues fans earlier this month after a disappointing showing in the 2-1 defeat by Tottenham Hotspur, with the supporters saying he has regressed.