Julen Lopetegui is facing two make-or-break games at West Ham, who have used the international break to explore potential replacements. Although the club are clinging on to the hope the Spaniard can turn the situation around, belief in the manager is fading and there is a serious prospect of him being fired this month.

It is understood much will depend on how West Ham fare when they visit Newcastle on Monday and host Arsenal on Saturday week. Defeats in those matches are likely to have serious ramifications for Lopetegui, who is under extreme pressure after a poor start. There is even the possibility of a heavy defeat by Newcastle forcing West Ham’s hand.

David Sullivan, West Ham’s largest shareholder, has been reluctant to make mid-season firings. But alarm over the performances under Lopetegui is growing and it is understood talks have been held over making a change.

West Ham, who are five points above the bottom three after winning three of their 11 games, are not thought to have decided on a preferred replacement for Lopetegui, who succeeded David Moyes last summer. They have looked at the former Borussia Dortmund manager Edin Terzic, and have made internal checks on former Denmark coach Kasper Hjulmand, former Benfica coach Roger Schmidt and Stuttgart’s Sebastian Hoeness. The Guardian understands there are others coaches in the running. Long- and short-term appointments are being considered. Graham Potter, the former Chelsea manager, is available but West Ham have never seemed drawn to him.

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The atmosphere at the London Stadium was muted when West Ham were held to a goalless draw by Everton in their most recent game. Star players are not performing and questions have been raised over Lopetegui’s tactics. The football has been drab, new players have not settled and there have been disciplinary issues. Disquiet over recruitment has also led to focus on the technical director, Tim Steidten. There have been reports that Steidten is cool on Lopetegui but it is understood the German was involved in the process that led to the 58-year-old’s appointment.

West Ham would prefer not to be pushed into sacking Lopetegui so soon. He is an experienced coach and has insisted that he will oversee an improvement given time. Lopetegui has previously managed Porto, Sevilla, Wolves, Spain and Real Madrid. He was available after leaving Wolves at the start of last season.