Naby Keita and Diogo Jota both scored in the opening 15 minutes before a Mohamed Salah hat-trick sealed a stunning victory for Liverpool.
United were outclassed by a superb Liverpool performance, with the Red Devils reduced to 10 men after Paul Pogba’s reckless challenge on Keita.
Ole Gunnar Solskjaer remains in charge of United, despite mounting pressure over his long-term future at Old Trafford.
Rooney has now claimed that it is “too easy for the manager to take all the stick” and believes the United players need to be held accountable for their performances.
Speaking to reporters, the Derby County manager said: “The Liverpool game wasn’t easy to watch.
“I’m seeing too many players not willing to run back, not willing to defend and not willing to put everything on the line for that club and that’s not acceptable.
“Those players need to be hurt, need to feel when you lose games how much it hurts you.
“There is a big responsibility on those players. They are world-class players, international players and a club like United need more.
“The players have to question themselves. It’s too easy for the manager to take all the stick when those players are being paid a lot of money to do the job and I don’t think they’re doing it well enough.”
Solskjaer, who signed a new United deal in July, reportedly has three matches to save his managerial career at Old Trafford.
Sir Alex Ferguson has put his backing behind the 48-year-old Norwegian, but the Scotsman has a No 1 choice for the next United manager if Solskjaer is sacked.
Former Inter Milan manager Antonio Conte and ex-Real Madrid head coach Zinedine Zidane have both been heavily linked with United amid growing uncertainty over Solskjaer’s future.
Rooney believes that former United teammate Solskjaer is a “fighter” and will continue to keep doing the “right things.”
The United legend said: “Obviously there’s pressure on Ole -- everyone can see that.
“But I know Ole and he’s a fighter. He’ll keep doing the right things, believing in what he believes in, and trying to get more out of those players.”
United will return to Premier League action on Saturday against Spurs at the Tottenham Hotspur Stadium.
Featured Image Credit: PA
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