The Red Devils signed Lukaku in a £75m deal from Premier League rivals Everton in the 2017 summer transfer window.
The Belgium international scored 10 times in his opening nine games at Old Trafford to hit the ground running.
Lukaku required another 29 games to hit the 20-goal mark to struggle during the festive schedule.
However, the 24-year-old has silenced some of his critics with impressive performances in victories over Chelsea FC and Liverpool FC.
Lukaku has netted seven times in his last 10 games in all competitions to help Manchester United reach the FA Cup semi-finals.
The Belgian forward started his career at Stamford Bridge to follow in the footsteps of his idol Drogba.
Former Spurs forward Crooks believes Lukaku is starting to look more like his hero Drogba as he grows in stature at Manchester United.
“Romelu Lukaku is looking more like Didier Drogba the more I see him,” Crooks told BBC Sport.
“From his first headed clearance on the edge of his own six-yard box, to his coolly taken opening goal, the United striker has had a resurgence in form and looks a powerhouse.
“I have seen him in this form for Everton, of course, but he is developing into a much better team player and manager Jose Mourinho must take the credit for that.”
Lukaku netted 24 times in 36 games in his final season at Everton before his big-money move to Manchester United last summer.
The Red Devils lost 2-1 to Spanish side Sevilla in the Champions League round of 16 earlier this month.
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