The striker scored the equaliser against Liverpool on Sunday to continue his fine form this season.
The striker was busy throughout the Merseyside derby on Sunday afternoon as he embarked on a one-man battle with the Reds backline, with Martin Skrtel providing a constant opponent throughout the game.
The Belgian was in fine form though, often coming out on top in a number of his duels with the Liverpool defence, and Shearer was full of praise for the display that the striker put in.
“His [Lukaku’s] game was complete today,” Shearer told Match of the Day.
“He did everything, holding it up, running in behind and causing the defence all kind of problems. I thought he had everything, I think the penny has dropped with him.”
The legendary Premier League striker has however insisted that the striker must now realise his potential and perform more consistently.
Lukaku has shown that he has the ability to be a top striker in the Premier League in his two seasons at Everton and one with West Brom, scoring a hatful of goals of both clubs over three seasons.
He has though, proved to be inconsistent, with one top performance, such as his one against Southampton earlier in the campaign, being followed by several less impressive displays.
And Shearer says he must now put in top performances eight or nine times out of ten to prove his ability.
“He is no longer the young kid signed for £28million from Chelsea,” added Shearer.
“He’s now the main man in the team, he’s a really good player if he wants to be and realises the potential he has. He’s now got to do that [performance] eight or nine times out of ten.”