West Ham's opening day of the new Premier League season couldn't have got off to a worse start, as they were battered and bruised by goals from Romelu Lukaku, Anthony Martial and Paul Pogba from a fit and firing Manchester United side at Old Trafford.
Right from the word go, Slaven Bilic's side took a backward step, allowing United to dominate the ball and venture forward at will. Offering a real threat on both flanks as well as down the middle, it was only a matter of time before the home side got their noses in front.
Romelu Lukaku announced his arrival in the best possible fashion, scoring either side of the half-time whistle as the scoreline began to reflect the vast divide in quality between the two teams.
The Belgian international latched onto a dangerous through ball by Marcus Rashford, smashing the ball off the post and into the back of the net at the first time of asking. It didn't take him long to double his tally in the second-half, either, glancing a header into the corner and beyond the reach of Joe Hart after Henrikh Mkhitaryan's free-kick.
The Hammers had a glimmer of hope when Marko Arnautovic flicked a header onto the top of the crossbar at 2-0 before goals from Anthony Martial and Paul Pogba rounded off a comfortable 4-0 victory.
West Ham not at the races on the opening day of the season
No West Ham fan would've headed into the game with much optimism against United nor would they have expected to see their side struggle to challenge for the first, or even second ball. Registering just one shot on target speaks volumes about the manner of their performance, with Bilic's side showing no spark or intent to bring the game to Mourinho when they fell behind.
The opening half hour was steady, with the defensive shape and formation holding up well to provide a resolute resistance against United's forward verve but as soon as Pablo Zabaleta was caught out of position, alarms bells went off.
From then on, there was no going back. West Ham were unable to get any kind of foothold on the game, with the midfielders looking rigid and poor in possession having expelled so much energy previously.
Surrending possession and positioning far too easily, West Ham were never at the races on the opening day of their 2017/18 Premier League campaign, leaving Slaven Bilic with plenty to think about ahead of their next game.
No forward momentum as Javier Hernandez cut a frustrated figure
The visitors only had two real chances in the entire game, with Andre Ayew colliding with his teammate on the edge of the area to stifle what could otherwise have been a dangerous shot on David De Gea's goal. With the score only 1-0 at the time, it could have been a very different story had West Ham taken their golden chance.
As it panned out, though, the United goalkeeper was able to make a routine save to ensure his side went in ahead at the break.
The second-half brought similar fortunes, with the best chance coming after Lukaku glanced in the ball from eight yards out to double the home side's advantage. Edmilson Fernandes delivered a teasing ball into the box that found the head of Arnautovic. The former Stoke City forward got the wrong side of Daley Blind but his header narrowly missed the target.
Given their summer recruits, especially in the shape of Arnautovic, West Ham showed a worring lack of forward momentum and creativity at Old Trafford, leaving Javier Hernandez as a very lonely figure upfront.
Injuries cause West Ham problems all over the shop
West Ham were clearly affected by injuries heading into the game, with star man Manuel Lanzini unavailable after picking up a knock alongside Kouyate and Andy Carroll - all of whom would arguably fit straight into the starting eleven.
Given the team's reliability on Lanzini to provide the creativity in midfield, the Hammers were always going to struggle to muster up a consistent attacking threat in his absence, but it will serve as a warning to Bilic in the games to come should the Argentinian be ruled out for a sustained period.
Michail Antonio, the club's top goalscorer last season, was also out of action with a hamstring issue which only made matters worse ahead of an already hard task at Old Trafford.