Manchester City underlined the vast gulf in quality between themselves and Manchester United on Sunday as Liverpool showed their support for absent teammate Luis Diaz, whose parents were kidnapped in Colombia.
Liverpool's Diogo Jota holds up a shirt in support of Luis Diaz after scoring a goal on Sunday. - Reuters
Old Trafford paid tribute to late United great Bobby Charlton ahead of kick-off, with supporters unfurling a banner that read: "The finest English footballer the world has ever seen".
But memories of past glories failed to translate onto the pitch, with the home team thoroughly outplayed by the champions, who did not have to get out of second gear in their 3-0 win.
Champions City made most of the early running and were awarded a penalty after VAR spotted a foul on Rodri by Rasmus Hojlund as the ball was crossed into the area from a free-kick.
It was the first spot-kick Manchester City have ever been awarded at Old Trafford in the Premier League in the 27th meeting between the teams.
Erling Haaland stepped up to tuck home from the spot, his 12th goal of the season in all competitions.
City goalkeeper Ederson saved a Scott McTominay pile-driver before Andre Onana produced heroics at the other end when Haaland appeared certain to head home.
But the Norwegian forward made no mistake just after the break, thumping home a header from Bernardo Silva's cross.
Phil Foden made it 3-0 with 10 minutes remaining after he was set up by Haaland.
Earlier, Liverpool swept Nottingham Forest aside by the same scoreline.
Goals from Diogo Jota and Darwin Nunez before the break and Mohamed Salah's second-half effort ensured Jurgen Klopp's side maintain their 100 percent home record in the Premier League this season.
Jota held aloft Diaz's number seven shirt after scoring -- the Colombian did not feature in Liverpool's squad following the kidnapping incident in his home country.
Colombia President Gustavo Petro said on Saturday that the winger's mother had been rescued but the search remained ongoing for his father.
"Luis was with us in the hotel then he went home," Jota told the BBC. "It's a very hard situation and I don't know how anyone would react if it happened to you.
"He was going to play. I played instead of him, and I showed him his shirt to show we're with him and we hope everything works out."
Liverpool finished the day fourth in the table, behind leaders Tottenham, Arsenal and City.
High-flying Aston Villa, in fifth spot, won their 12th consecutive home game in the Premier League, beating struggling Luton 3-1.
Unai Emery's side made light work of their opponents, with goals from John McGinn and Moussa Diaby giving them the upper hand before Luton captain Tom Lockyer put through his own net.
"For me it is still a long process here and I will want to work to improve as always," Emery told Sky Sports.
"Of course I am happy but still being serious, serious in the way I want to build here and improve more."
Brighton lost further ground after their sparkling start to the season.
The south coast club took a 1-0 lead through Evan Ferguson, but Fulham levelled through midfielder Joao Palhinha.
Dominic Calvert-Lewin scored the only goal of the game as Everton beat West Ham 1-0 to give themselves breathing space above the relegation zone.