The Spain international moved to Chelsea in a £58m deal from Champions League holders Real Madrid last month to bolster Antonio Conte’s attacking options.
Morata made a disappointing start to his Blues career after the 24-year-old striker missed his spot-kick in Chelsea’s penalty shootout loss to Arsenal in the Community Shield.
The Blues striker was named on the bench for Chelsea’s opening game of their title defence as Belgian forward Michy Batshuayi started up front for the champions.
However, manager Conte turned to Morata in the 59th minute with the west London side trailing 3-0 to Burnley at Stamford Bridge following Gary Cahill’s sending off.
And Morata opened his Premier League account within 10 minutes of his introduction with a precise finish to give the hosts faint hope of a comeback.
The striker provided the assist for David Luiz to score a second goal for Chelsea in the final two minutes of normal time.
Former Barcelona and Tottenham striker Lineker reacted to Morata’s first Chelsea goal before Cesc Fabregas was sent off for a second bookable offence to leave the title holders with nine men.
Lineker wrote on Twitter: “Morata scores on his @premierleague debut. If he gets 4 this will be one hell of a game.”
Stephen Ward scored a wonder goal sandwiched between Sam Vokes’ two goals for Burnley at Stamford Bridge.
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