At this point, Lukaku and Rooney have the same amount of Premier League goals.
His last goal for United in the league was last month in the 4-1 win over Newcastle.
The forward has failed to recreate his early-season form that resulted in 10 goals in his opening nine matches for the Red Devils.
Jose Mourinho swore at Ederson and someone drew blood from Mikel Arteta's lovely face in the aftermath of City's 2-1 win over United at Old Trafford.
'No one was asking the question of Mourinho then and whether he had improved Lukaku.
"He's not doing enough in games-and I hate saying it-to justify his fee".
There have been suggestions from pundits and former professionals that he is clearly lacking on confidence. "Everything seems a second or two too slow and by the time he's made his mind up it's gone".
Shearer also scrutinised Lukaku's performance in front of goal.
The Portuguese tactician was in a furious mood when faced with questions about the clash between Manchester United and Manchester City players after their meeting at Old Trafford on Sunday and he was enraged at questions about his star striker. "I'm not just talking about struggling in terms of missing a chance, he struggled at being in the game and being confident in the game".
Likewise, those chances have not been so easy to come by in recent months, as United have been without Paul Pogba, who was out with a hamstring injury between September and mid-November and then missed the City match after he picked up a red card against Arsenal on December 2.