Going to Merseyside, expecting to be underdogs, the East London club started well, with a period of 10 minutes or so when there was slight hope within the West Ham fan base.
However, just before the 20th-minute mark, Mo Salah opened the scoring tapping in after an excellent Andy Robertson cross. The result looked all but certain with Sadio Mane putting the reds 2-0 just before the halftime break.
A half-time change of Declan Rice replaced by Robert Snodgrass, gave brief hope for the Hammers until Mane scored his second of the afternoon in the 53rd minute.
A bad day at the office for United, which was made worse when Daniel Sturridge scored on his Liverpool return from close range, a matter of seconds since entering the field.
Poor defence dismantled
Lukasz Fabianski - 6/10:
An impressive debut and barely at fault for the goals. Unfortunately for him, Liverpool's attack were too much for his defence which ultimately led to goals he couldn't prevent.
Ryan Fredericks - 4/10:
Really struggled on his Premier League debut, was completely outclassed by Sadio Mane. With Andy Robertson's outside runs and lack of help from his teammates, at some points felt sorry for the right-backs efforts.
Fabian Balbuena - 6/10:
Was helpless when trying to prevent the movement with the Liverpool frontline, however, asserted himself when in the game and was a good start to his Premier League career.
Anglelo Ogbonna - 4/10:
At times managed well with the Red's attack using his pace and power, however, after several mistakes and what seemed a lack of focus, was eventually punished.
Arthur Masuaku - 2/10:
A liability for West Ham as he struggled defensively and offensively. Couldn't handle Mo Salah's pace and potentially at blame for 2 of the Liverpool goals. The left-backs dire performance could be down to the sheer quality of Salah, however.
Outclassed by Liverpool energetic midfield
Mark Noble - 5/10:
Liverpool's central movement was too much to contain despite the captain's efforts. Noble tried to kickstart attacks but attempts were stopped by a high pressure and dominant Reds midfield.
Declan Rice - 3/10:
After struggling to adapt to the match tempo and energy of Naby Keita. The youngster was hauled off at half-time, a good learning curve for the midfielder.
Jack Wilshere - 6/10:
Tried to get the ball moving for the hammers but was constantly outnumbered within the midfield and pushed off the ball. A lot of energy to no real end product, unfortunately.
Michail Antonio - 4/10:
Made little to no impact other than a vital last-ditch tackle in the box to nick the ball from Firmino who was set to score. Lost the ball multiple times and didn't really seem to get into the game.
Felipe Anderson - 6/10:
The silky Brazillian was the Hammers most influential and offensive threat. Didn't see as much as the ball as he should've but when given the chance showed potential and willing to run with the ball.
Ineffective and isolated
Marko Arnautovic - 5/10:
Started the game well and scuffed a couple of chances but was quickly isolated ad West Ham struggled to give him any support up top. Walked off gingerly after 70 minutes replaced by new signing Yarmolenko.