The defending Premier League champions were heavily linked with a move to sign Lukaku in the summer transfer window but Manchester United managed to hijack a £75m deal for the Everton striker.
Spain international Morata was initially linked with the Red Devils after it emerged Antoine Griezmann would not be leaving Atletico Madrid in the summer transfer window.
Chelsea decided to sign the 24-year-old striker in a £58m deal from Real Madrid as Antonio Conte looked to find a replacement for controversial Diego Costa.
Lukaku has hit the ground running with five goals in five games to help Manchester United make impressive starts in the Champions League and the Premier League.
Morata, on the other hand, has scored against Burnley, Everton and Leicester City to surprise some of his critics with an instant impact in the English top flight.
Former Chelsea defender Le Saux claimed that Lukaku is a superior striker to Morata despite the Spanish forward’s impressive performances for the reigning champions so far.
“Chelsea were obviously in for Romelu Lukaku in the summer and missed out, but Alvaro Morata is certainly doing enough to justify his transfer fee,” Le Saux told Betfair.
“At the moment you might say that Lukaku is the better striker, based on amount of goals scored.”
Manchester United started the Premier League weekend in top spot following a return of 10 points from four games.
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