West Ham slipped to their first Europa League defeat of the season as they were narrowly beaten at Olympiakos.
Kostas Fortounis surged through the West Ham defence and struck from 25 yards to open the scoring.
Angelo Ogbonna then turned into his own net just before the break to further deflate the Irons.
Lucas Paqueta’s brilliant volley in the 87th minute came too late with the Hammers unable to salvage something from the game.
David Moyes’ side remain top of Group A despite losing.
Olympiakos started brightly, Sotiris Alexandropoulos’ early effort forcing Alphonse Areola to save low down to his left.
The home side were winless in their past 11 Europa League games, their longest run without victory in major European competition, but there was no lack of confidence against West Ham.
The Hammers dominated possession but looked disjointed throughout, with Said Benrahma firing against the side-netting in the early stages.
James Ward-Prowse whipped a promising free-kick wide of the post, while Danny Ings got on the end of a corner but could not keep his header down and it nestled on the roof of the net.
Irons’ European unbeaten record ends frustratingly
West Ham became the first English side to go 17 consecutive games in European competition without defeat when they won at Freiburg this month.
However, they looked lacklustre from the start in Greece with seven changes made from the team that lost 4-1 at Aston Villa on Sunday.
“Look, we changed a lot of players tonight, we’ve got the Premier League coming up and we’ve got a League Cup game next week and we’d won the first two games in the group, which gave us leeway to make changes tonight,” Moyes told whufc.com.
“I don’t think anybody could say the team we started with wasn’t a good team and wasn’t a team capable of winning or performing.
“Many of them have been very good players for us over the years and still are.”
Buoyed by a raucous home crowd, Olympiakos were on the front foot from the outset and had two early corners to show their intent.
Poor defending was to blame for both first-half goals, Konstantinos Mavropanos affording Fortounis space, whose brilliant individual effort was struck home from the edge of the box.
Ogbonna then flicked his leg at the ball following a hopeful cross swung in by Rodinei as West Ham conceded two goals in the last 15 minutes of the first half.
Paqueta halved the deficit with a superb left-footed volley into the bottom corner after Michail Antonio’s cross was only half cleared, but it was too little, too late as Moyes’ side were made to pay for an ineffectual display away from home.
This was just West Ham’s second group-stage defeat in nine such matches, and they will look to get back to winning ways when they host Olympiakos on November 9.
Player of the match
Gustavo ScarpaGustavo Scarpa
Olympiakos
Squad number10Player nameGustavo Scarpa
Squad number56Player nameDaniel Podence
Squad number7Player nameFortounis
Squad number15Player nameAlexandropoulos
Squad number45Player nameRetsos
Squad number3Player nameOrtega
Squad number25Player namePorozo
Squad number9Player nameEl Kaabi
Squad number4Player nameCamara
Squad number1Player namePaschalakis
Squad number98Player nameSolbakken
Squad number23Player nameRodinei
Squad number18Player nameQuini
Squad number32Player nameHezze
Squad number22Player nameJovetic
Squad number19Player nameMasouras
West Ham United
Squad number7Player nameWard-Prowse
Squad number14Player nameKudus
Squad number20Player nameBowen
Squad number23Player nameAreola
Squad number10Player nameLucas Paquetá
Squad number19Player nameÁlvarez
Squad number33Player nameEmerson
Squad number24Player nameKehrer
Squad number15Player nameMavropanos
Squad number28Player nameSoucek
Squad number22Player nameBenrahma
Squad number8Player nameFornals
Squad number21Player nameOgbonna
Squad number17Player nameCornet
Squad number9Player nameAntonio
Squad number18Player nameIngs
Line-ups
Olympiakos
Formation 4-2-3-1
- 1Paschalakis
- 23de AlmeidaSubstituted forMarín Ruizat 75′minutes
- 25Porozo
- 45RetsosBooked at 47mins
- 3Ortega
- 32Hezze
- 4CamaraBooked at 82mins
- 56PodenceSubstituted forSolbakkenat 85′minutes
- 15AlexandropoulosBooked at 65minsSubstituted forMasourasat 85′minutesBooked at 90mins
- 7FortounisSubstituted forJoveticat 90+5′minutes
- 9El KaabiSubstituted forFurtado Scarpaat 90+5′minutes
Substitutes
- 10Furtado Scarpa
- 11El Arabi
- 17Vrousai
- 18Marín Ruiz
- 19Masouras
- 20Carvalho
- 21Biel Mas Jaume
- 22Jovetic
- 88Tzolakis
- 98Solbakken
- 99Papadoudis
West Ham
Formation 4-2-3-1
- 23Areola
- 24Kehrer
- 15Mavropanos
- 21OgbonnaBooked at 88mins
- 33EmersonBooked at 66mins
- 28Soucek
- 7Ward-ProwseSubstituted forÁlvarezat 72′minutes
- 14KudusSubstituted forCornetat 72′minutes
- 22BenrahmaSubstituted forBowenat 58′minutes
- 8FornalsSubstituted forLucas Paquetáat 57′minutesBooked at 64mins
- 18IngsSubstituted forAntonioat 58′minutesBooked at 76mins
Substitutes
- 2Johnson
- 3Cresswell
- 4Zouma
- 9Antonio
- 10Lucas Paquetá
- 17Cornet
- 19Álvarez
- 20Bowen
- 27Aguerd
- 45Mubama
- 49Anang
Live Text
Match ends, Olympiakos 2, West Ham United 1.
Second Half ends, Olympiakos 2, West Ham United 1.
Hand ball by Michail Antonio (West Ham United).
Konstantinos Tzolakis (Olympiakos) is shown the yellow card.
Attempt missed. Tomás Soucek (West Ham United) header from the centre of the box is just a bit too high. Assisted by Lucas Paquetá with a cross.
Substitution, Olympiakos. Stevan Jovetic replaces Konstantinos Fortounis.
Substitution, Olympiakos. Gustavo Scarpa replaces Ayoub El Kaabi.
Emerson (West Ham United) wins a free kick in the defensive half.
Foul by Ola Solbakken (Olympiakos).
Giorgos Masouras (Olympiakos) is shown the yellow card for a bad foul.
Edson Álvarez (West Ham United) wins a free kick in the defensive half.
Foul by Giorgos Masouras (Olympiakos).
Foul by Angelo Ogbonna (West Ham United).
Ayoub El Kaabi (Olympiakos) wins a free kick in the defensive half.
Attempt blocked. Maxwel Cornet (West Ham United) left footed shot from the centre of the box is blocked. Assisted by Michail Antonio.
Attempt missed. Konstantinos Fortounis (Olympiakos) right footed shot from outside the box is close, but misses to the right. Assisted by Jackson Porozo.
Delay over. They are ready to continue.
Angelo Ogbonna (West Ham United) is shown the yellow card.
Delay in match because of an injury Jackson Porozo (Olympiakos).
Goal! Olympiakos 2, West Ham United 1. Lucas Paquetá (West Ham United) left footed shot from outside the box to the bottom left corner.