The Manchester United striker headed home Juan Mata’s perfect centre to hand Jose Mourinho’s men all three points in a tight game, against an impressive Bournemouth side.
But there was no jubilation from the forward, who simply walked away before being mobbed by his team-mates.
It was the Belgian’s second goal in 10 Premier League games and the former Everton man has come under fire from sections of the Old Trafford support and media alike, with his confidence appearing to be affected.
Shearer admitted to being critical of Lukaku at the weekend, but speaking on Match of the Day he said he could not understand why Lukaku did not show more emotion after his first-half winner.
“Unless there is something we are unaware of, it was a very surprising lack of reaction from Lukaku to his goal,” said Shearer.
“Maybe that was in answer to the criticism he has been receiving. It was only his second Premier League goal in 10 games.
“I said something negative about him at the weekend, that he has to show more, but when you score that is the perfect answer.
“That is why I was surprised he did not run away, smile or put his arm in the air. It is such a fantastic feeling when you score goals, particularly the winning ones.”