Match ends, West Ham United 2, Brighton and Hove Albion 2.
Tomas Soucek scored a late equaliser as West Ham came from behind to rescue a point against struggling Brighton.
The Seagulls took the lead towards the end of a first half they dominated when Neal Maupay swept in at London Stadium.
West Ham improved after the break and equalised when Ben Johnson scored his first goal for the club, taking advantage of poor defending to finish from close range.
Lewis Dunk thought he had won it for Brighton when he smashed in his first goal of the season following a short corner.
But Soucek, not for the first time this season, came up with another crucial goal as the midfielder was left unmarked at a corner and powered home a header.
Brighton had to settle for a fifth draw in their past eight games and are just two points above the relegation zone in 16th.
West Ham, meanwhile, remain 10th but move on to 22 points.
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West Ham recover after dreadful first half
David Moyes has fashioned a very decent West Ham side that is disciplined while often creative and attack-minded. They have been rewarded for their enterprising play with some impressive results, notably big wins against Wolves and Leicester and draws at Manchester City and Tottenham.
It was therefore perplexing that Moyes appeared to abandon that approach with a very negative team selection and set-up against Brighton.
The Hammers were dreadful in the first half as they failed to register a shot on target and deservedly found themselves behind.
After the break, they were a different side. The introduction of Andriy Yarmolenko and Manuel Lanzini added the creative spark that had been missing and they took advantage of a Brighton side that struggled for composure after losing Adam Lallana to injury.
Had Moyes shown more faith in his side's attacking capabilities from the start, they may have got more reward than the single point. The second-half performance will likely give him plenty to think about when setting up his side for similar games in the future.
Seagulls' winless run continues
This has been a frustrating season for Brighton, who have often failed to get the reward their good play and possessional dominance has merited.
It was a similar story against West Ham, particularly in the first half when they were comfortably the better side and arguably should have had more than Maupay's goal to show for it.
It was always likely to be tougher in the second half, and credit should be given to the Seagulls for twice getting in front, but their defending for both the goals they conceded was disappointing. They failed to make the most of numerous opportunities to clear for West Ham's first and then left the obvious threat of Soucek unchecked for the second.
It is now just one victory in their past 14 games for Brighton and while a point at a solid West Ham side is a good result, the Seagulls need to find a way to get wins on the board again soon to avoid getting properly dragged into a battle for Premier League survival.
'Frustration is the emotion' - what they said
West Ham manager David Moyes told BBC Sport: "We saw a poor West Ham in the first half but we also saw a good Brighton team in the first half. They made it difficult for us but the resilience of the players kept us going and a few changes helped us.
"We thought it was the right time to have a look at a back five again but I felt we didn't press them well enough. Lanzini has been an important player for us in recent years and I'm hoping to get him back to the levels he has been because he is a talented player and we needed that."
Brighton manager Graham Potter told BBC Sport: "Frustration is the emotion at the moment. We felt we did enough for three points but the second goal is the one that has punished us, and if you don't defend that situation better, you come away with just one point.
"Over the course of the game, I felt we did a lot well, particularity in the first half. It is hard to control 90 minutes of a Premier League game. You have to accept the opposition will step forward and show some momentum. After the goal, we felt more in control and to see it out better is the thing we have to improve on."
Johnson the youngest since Januzaj - the stats
- Brighton remain unbeaten against West Ham in the Premier League, although each of the past four meetings in the competition have ended level.
- West Ham are winless in their past three Premier Leagues games at London Stadium, equalling their longest run without a win there since David Moyes returned to the club (three games between January and February).
- Since his Premier League debut in February, no player has scored more headed goals in the competition than West Ham's Tomas Soucek (four, level with Dominic Calvert-Lewin and Harry Kane).
- West Ham's Ben Johnson was the youngest player to score in the Premier League for a David Moyes side since April 2014, when Adnan Januzaj netted for Manchester United against Newcastle (aged 19 years and 59 days).
- Neal Maupay's opener for Brighton saw him end a run of 649 minutes without a goal in the Premier League - the Frenchman now has 15 goals for the Seagulls in the competition, with only Glenn Murray netting more (26).
- Five of Lewis Dunk's seven goals in the Premier League for Brighton have been scored from corners, while all seven have been from a set-piece situation.
West Ham travel to Southampton on Tuesday, 29 December (18:00 GMT), while Brighton host Arsenal at the same time.
- 16NobleSubstituted forLanziniat 45'minutes
- 20BowenSubstituted forYarmolenkoat 45'minutes
- 14LallanaSubstituted forAlzateat 45'minutes
- 9MaupaySubstituted forJahanbakhshat 90'minutes
- 18WelbeckSubstituted forGroßat 83'minutes
- 10Mac Allister
- Simon Hooper
- Shots on Target
Second Half ends, West Ham United 2, Brighton and Hove Albion 2.
Foul by Yves Bissouma (Brighton and Hove Albion).
Tomas Soucek (West Ham United) wins a free kick in the attacking half.
Hand ball by Tomas Soucek (West Ham United).
Attempt saved. Tomas Soucek (West Ham United) header from the left side of the six yard box is saved in the top centre of the goal. Assisted by Vladimir Coufal with a cross.
Substitution, Brighton and Hove Albion. Alireza Jahanbakhsh replaces Neal Maupay.
Attempt blocked. Vladimir Coufal (West Ham United) right footed shot from the right side of the box is blocked.
Attempt blocked. Tomas Soucek (West Ham United) left footed shot from the centre of the box is blocked. Assisted by Sébastien Haller.
Foul by Adam Webster (Brighton and Hove Albion).
Sébastien Haller (West Ham United) wins a free kick in the attacking half.
Attempt missed. Solly March (Brighton and Hove Albion) left footed shot from the left side of the box misses to the right. Assisted by Leandro Trossard.
Attempt missed. Leandro Trossard (Brighton and Hove Albion) header from the centre of the box misses to the left. Assisted by Pascal Groß with a cross.
Substitution, Brighton and Hove Albion. Pascal Groß replaces Danny Welbeck.
Goal! West Ham United 2, Brighton and Hove Albion 2. Tomas Soucek (West Ham United) header from very close range to the bottom left corner following a corner.
Corner, West Ham United. Conceded by Dan Burn.
Foul by Lewis Dunk (Brighton and Hove Albion).
Sébastien Haller (West Ham United) wins a free kick in the attacking half.
VAR Decision: Goal Brighton and Hove Albion - West Ham United 1-2 Brighton and Hove Albion (Lewis Dunk).
Goal! West Ham United 1, Brighton and Hove Albion 2. Lewis Dunk (Brighton and Hove Albion) right footed shot from the left side of the six yard box to the top left corner following a corner.Goal confirmed following VAR Review.
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