Jadon Sancho scored the first goal of the Ten Hag era, smashing home from inside the penalty area after just 12 minutes.
Fred then produced a moment of Brazilian brilliance to double United’s advantage, as the ball fell kindly to the midfielder, who lofted his effort over Alisson and into the net.
Anthony Martial added a third soon after, as the Reds really took charge during the game’s first period. The Frenchman picked the pocket of Rhys Williams before racing through to lift the ball beyond the advancing Alisson.
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As the second half began, both teams opted to make wholesale changes in the blistering heat at the Rajamangala Stadium.
David De Gea was the only Red who stayed on but was withdrawn just after the hour mark, while there was also a maiden appearance for our newest recruit Tyrell Malacia.
Returning loanees Donny van de Beek, Amad and Facundo Pellistri all featured for United, with the latter rounding off the scoring with 15 minutes to go.
Eric Bailly charged forward from defence, before Amad squared for Pellistri, who netted our fourth of the game with a composed finish past Adrian. Liverpool had their chances and hit the woodwork on a couple of occasions, including one curling attempt by Mohamed Salah, while Diogo Dalot struck the outside of a post for United.
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