Everton will probably look back on a period directly after half-time and wonder what-if after Rafa Benitez’s side suffered their first Goodson Park defeat of the season.
The hosts generated some attacking momentum immediately after the restart and both Alex Iwobi and Salomon Rondon were close to scoring.
Iwobi’s penalty-box strike was blocked by eventual matchwinner Angelo Ogbonna and Rondon flicked a header past the post from Andros Townsend’s latest menacing delivery.
But the margins, typically, are fine in Premier League football – Everton had 15 attempts to their opponents’ 16 – and it was West Ham that finished on the right side of scoreline.
The visitors’ threat appeared to have dimmed when they forced their goal for Italian defender Ogbonna with 16 minutes remaining.
The concession was especially disappointing for Everton who emphatically contested the award of the corner from which it was scored.
Ben Godfrey’s outstretched leg prevented Jarrod Bowen’s cross from reaching Michael Antoino and sent the ball spinning into the air.
Antonio made his presence felt as Jordan Pickford sought to tidy up and the ball crossed the byline.
Everton wanted either a free-kick for Antonio’s challenge on Pickford, or a goalkick, claiming the ball hit the West Ham player before spilling behind.
Referee Stuart Attwell gave the corner and Bowen swung it in from the right. Ogbonna was first to the near post and his headed connection sent the ball flying beyond Pickford and into the far corner.
West Ham’s boisterous away supporters thought their team had claimed the lead after 34 minutes.
In fact, it might have looked from the other end of the stadium as if Bowen’s strike from 10 yards was destined for the back of the net.
Pickford, however, was down in a flash to push the ball away to his left.
Then the eruption from a corner of Bullens Road, as Tomas Soucek slid to turn the rebound into the roof of the net.
You need to pivot your neck 90 degrees to see along the touchline from that part of the stadium, so it was only a minority of the Londoners inside Goodison who saw the linesman’s flag correctly pointing out Soucek had strayed offside before converting.
That episode rekindled the Hammers’ spark nonetheless.
Everton had taken a while to get going in an offensive sense. It was minute 16 when Seamus Coleman sped away from Pablo Fornals to steer a pass to Rondon. His layoff found Townsend, who whipped a peach of a ball to the far post where Iwobi arrived a fraction too late to take advantage.
Another Townsend cross 17 minutes later, this one stood up from the byline with his right foot after escaping Declan Rice, was met by Abdoulaye Doucoure, leaping but unable to find the direction to trouble Lukasz Fabianski.
Doucoure had lashed over earlier on after Aaron Cresswell headed out a cross from Lucas Digne and, not long after, the Everton midfielder dextrously spun close to the byline to feed Iwobi for a shot that flew into a crowd of defensive bodies. The latter move was started by a gorgeous outside-of-the-boot layoff from Demarai Gray that drew audible gasps from all over Goodison.
Gray had been Everton’s most promising outlet during an opening when they saw little of the ball, the former Leicester City player a banker to retain possession regardless of the number of opponents keeping him company.
And he had the chance to inject some forward thrust on 28 minutes. He took it, of course, leaving Ogbonna standing but seeing Iwobi miss his kick when the ball travelled across the face of goal.
Midway through the opening 45 minutes, the numbers showed West Ham with 80 percent of the ball.
But for all their possession, the away team had struggled for clear openings.
Everton were penned back for extended periods, sure, but repeatedly slammed the door in their opponents’ faces.
Indeed, the Hammers’ attacks – save for Cresswell’s devilish cross after three minutes that eluded Antonio at the back post – followed a similar pattern.
The ball was zipped about with speed and intent, as West Ham’s midfielders and forward players darted this way and that. But Everton retained their shape and concentration to intervene at the clutch moments.
Coleman stole in front of Fornals after right-sider Bowen reached the byline to cross and there was a carbon copy on the opposite side when Digne intercepted following Said Benrahma’s weaving run into the box and square pass.
Ben Godfrey, restored to centre-half with Yerry Mina on the bench following his international exploits 5,000 miles away in Colombia barely 72 hours ago, was in the way when Fornals connected with a volley in front of goal.
And when a Godfrey clearance landed at the feet of Benrahma, the squat, skilful forward was off-balance and struck over.
West Ham weren’t without their disciplinary issues in the opening 45 minutes. Fornals was cautioned for arriving late into a challenge on Townsend, the Spaniard joining Antonio in the book after the striker tumbled over despite the tracking Michael Keane withdrawing his foot from a tackle.
Cresswell was perfectly positioned to clear with Gray poised to connect when Iwobi burst down the left and cut a ball back into the box just past the half hour.
West Ham, though, bookended the ofirst half with periods on top.
Docuoure blocked from Bowen and when Fornals got hold of the rebound it needed Godfrey to put his body on the line to intercept.
The cunning Fornals again, soon after, scheming and dodging to create space to shoot from 18 yards but curling narrowly off-target.
The action immediately after the restart bore no resemblance to what followed kick-off.
Everton looked the more likely and twice inside five minutes were close to a breaktrough.
Gray slid a ball from left to right that meandered through the six-yard box without any takers.
Digne raced down the left to supply Iwobi, who turned sharply but saw his shot diverted behind by Angelo Ogbonna.
Then another Townsend delivery, flat from the right, but glanced wide of the far post by the diving Rondon.
A lull, then after 63 minutes, after Iwobi’s own cross alighted back at his feet, an effort fired wide on Fabianski’s right.
There hadn’t been a whole lot from West Ham in the second half until its midway point.
But they sprung into life through Antonio whose fizzing strike was bravely repelled by Michael Keane.
And after Antonio caused confusion to win a corner on 74 minutes, Ogbonna met Bowen’s corner to flick West Ham in front.
Everton tried to retaliate through Godfrey, who volleyed over from a Gray corner, but Pickford had to be at full-stretch to save one handed when Bowen aimed for the far corner following a rapid West Ham break.
Ogbonna did exceptionally well to throw himself in the way of a goalbound effort from Gray in stoppage time.
There was a final push from the home side but West Ham battened down the hatches and claimed the points by the smallest of margins.