The 29-year-old scored his first Premier League goal since December 2023 in Man City’s 2-0 Premier League win over Leicester on Wednesday.
Grealish has been linked with a move away from the club in the summer after failing to nail down a starting spot since his move back in 2021.
Speaking to Betfair, Shearer believes he knows exactly why the England international has failed to live up to the hype at City.
Shearer said: "I don't know what goes on inside the walls of Man City. Whether Pep doesn't like his (Grealish) attitude or he doesn't like what he's seeing on the training pitch I don't know.
“All I do know is that Jack is a really good lad who cares for his family massively, loves his football and loves a good time.
"I couldn't comment on whether he's been treated unfairly or not but what I do see is a really caring, sensitive person who needs loving.
“Jack is also someone who loves football and if he's not playing then I can appreciate that he hurts. Jack will want the next game to come today because he'll be on a high, he'll be buzzing.
“I listened to his emotional interview after the game and it's now a really good opportunity for him to stamp his authority on the Man City team again with Haaland out injured.
"Goals do wonders for confidence so he'll be flying now and he'll be so excited for the next game and will want Pep to put him in.
“You know what it's like when you haven't scored in so long. You get one and then more come along so don't be surprised if he scores again at the weekend as well.
"Jack would've been hurting after not getting a call-up for England. He'll have looked at who was picked, looked at their performances and the goals that have been scored and it will have hurt him but there's only one thing to do as an individual - you have to go out, perform and hopefully for his sake this is the start of a really good run for him."