The Red Devils signed Lukaku in a £75m deal from Premier League rivals Everton in the summer transfer window.
Lukaku was signed to bolster Jose Mourinho’s attacking options for the 2017-18 campaign following Wayne Rooney’s departure.
The 24-year-old has scored seven times in seven games in the Premier League and has netted three goals in two appearances in the Champions League.
Lukaku moved to Chelsea from Anderlecht in 2011 and was signed as a long-term replace for Blues striker Drogba.
While the Belgium international failed to realise his talent at Stamford Bridge, Lukaku looks set to become a firm favourite at Old Trafford.
Former Manchester City defender Mills sees similarities between Lukaku and Drogba.
“Lukaku is the Drogba type striker,” Mills told BBC Radio 5 Live.
“He is a target man. He is going to bully defenders. He is going to score goals where he bursts down the channel.”
Manchester United were 4-1 winners against CSKA Moscow thanks in part to Lukaku’s two goals.
The summer signing continued his goal-scoring run with a close-range finish in Saturday’s 4-0 victory over Crystal Palace.
The Red Devils forward has netted 11 times in all competitions in the 2017-18 season so far.
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