The Spain international has struggled with his form in recent weeks in the Premier League following the summer signing’s return from a hamstring problem at the start of October.
Morata was named in Antonio Conte’s starting line-up for the visit of former manager Jose Mourinho and the Manchester United team despite failing to score since a 4-0 win at Stoke City in September.
However, the 24-year-old striker netted a 55th-minute winner with a brilliant header to help Chelsea secure a 1-0 win against bitter title rivals Manchester United.
Morata has now scored seven goals in 10 games in the Premier League to make a good start to his Chelsea career.
“There were so many positives in terms of performances as well of course and you could do a lot worse than start with considering Alvaro Morata who suddenly rediscovered his stunning form from before his injury,” Nevin told Chelsea’s website.
“Three United centre-backs working together couldn’t get close to dealing with him. The skill, the power, the pace and the vision were from somewhere well above the very top drawer.
“After his recent missed chances and his substitutions, it could be something as simple as having full match-fitness again at last and total belief that the injury to his hamstring was not about to suddenly resurrect its ugly head.”
Morata has now scored seven of Chelsea’s 19 goals in the Premier League this season following his club-record move to Stamford Bridge in the summer transfer window.
The Spanish forward was linked with a move to Manchester United in the summer before Mourinho opted to sign Belgian forward Romelu Lukaku from Everton in a £75m transfer.
Chelsea are nine points adrift of Premier League leaders Manchester City.
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