Cristiano Ronaldo marked his second debut for Manchester United with two goals in a 4-1 victory over Newcastle United.
Man Utd started brightly, with Ronaldo and Raphael Varane both going close.
The hosts took the lead in first-half stoppage time, Ronaldo tapping in after Freddie Woodman had spilled Mason Greenwood's deflected shot.
Javier Manquillo stunned Old Trafford in the 56th minute when he equalised for Newcastle with a low angled drive after a terrific counter-attack led by Miguel Almiron.
But Man Utd responded and were back in front six minutes later as Luke Shaw drove forward and played in Ronaldo, whose shot was too powerful for Woodman.
Bruno Fernandes took a pass from Paul Pogba and hammered into the top corner from 25 yards to make it 3-1 with 10 minutes remaining.
Jesse Lingard came on to curl in a fourth in stoppage time as United went top of the table with 10 points, ahead of Chelsea on goals scored.
Newcastle sit 19th on one point.
See: Man Utd report | Newcastle report
Next fixtures
Man Utd: 19 Sep v West Ham (A)
Newcastle: 17 Sep v Leeds (H)
Match officials
Referee: Anthony Taylor. Assistants: Gary Beswick, Adam Nunn. Fourth official: John Brooks. VAR: Craig Pawson. Assistant VAR: Scott Ledger.
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