The Red Devils forward endured a miserable Manchester derby to prompt criticism of the summer signing following a tough couple of months for the Belgium international.
Lukaku played a role in both of Manchester City’s goals on Sunday evening as Pep Guardiola’s side were 2-1 winners against Manchester United to leave Jose Mourinho’s men 11 points adrift of the leaders.
The 24-year-old got on the end of Juan Mata’s cross to steer a header past Bournemouth goalkeeper Asmir Begovic at Old Trafford.
Lukaku didn’t celebrate his ninth Premier League goal of the season in a clear message to the Manchester United striker’s critics.
And former Middlesbrough midfielder Mustoe felt Lukaku’s lack of celebration was a clear signal from the Belgian to his detractors.
“He needed a goal. It is a typical Romelu Lukaku goal,” Mustoe told NBC Sport. “It was a marvellous header into the goal.”
Lukaku scored 25 goals in 36 games in all competitions during his final season at Everton before his big money move to Manchester United.
The Red Devils haven’t won the Premier League title since Robin van Persie scored 26 times in 38 games in their successful 2012-13 campaign under Sir Alex Ferguson.
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