West Ham are considering Sérgio Conceição as a replacement for Julen Lopetegui, whose future as manager is under growing pressure after his team’s 5-2 defeat at home against Arsenal last Saturday.

The Guardian revealed last month that the Spaniard’s position hinged on results against ­Newcastle and Arsenal, with defeats in both ­outings likely to have resulted in his dismissal. Lopetegui, hired as David Moyes’s replacement last summer, met the challenge by recording an impressive 2-0 win at Newcastle.

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Yet West Ham were unable to build on that performance when they hosted Arsenal, who sailed into a 4-0 lead inside 36 minutes after capitalising on some woeful defending. The manner of that latest collapse has placed Lopetegui under renewed scrutiny before the trip to Leicester on Tuesday night and the home game against Wolves next Monday. Although beating Newcastle has bought the 58-year-old time, it is understood West Ham have been identifying potential replacements.

There is serious interest in Conceição, who left Porto last summer. The 50-year-old Portuguese, who led Porto to three league titles and twice took them to the Champions League quarter-finals, is thought to be attracted to the job. West Ham are yet to establish contact with Conceição but there is support for him within the club.

Other contenders include the former Juventus manager Max Allegri, who has been pictured in London recently. There is a feeling that ­Graham Potter could come into contention. The former Paris Saint-Germain manager Christophe Galtier, who is coaching Al-Duhail in Qatar, has been considered in the past.

West Ham, six points above the bottom three, are yet to advance interest in Edin Terzic, the former Borussia Dortmund manager. They have made checks on Kasper Hjulmand, Roger Schmidt and Stuttgart’s Sebastian Hoeness.

West Ham do not have a history of swift sackings and remain reluctant to fire Lopetegui but there is growing alarm over the team’s form. The former Wolves manager has struggled to implement his vision and there is disquiet over last summer’s transfer business. West Ham spent more than £100m on players. Questions have been asked about Tim Steidten, the technical director.

Lopetegui could be in serious trouble if West Ham lose against Leicester. He has been boosted by the availability of Lucas Paquetá who had been expected to give evidence in São Paulo on Tuesday to the Brazilian parliament for its inquiry into sports betting. The midfielder’s legal team successfully argued for him to appear via a remote video link.

However it has emerged that Paquetá, who has been charged by the Football Association over an alleged breach of its betting regulations, is not obliged to give evidence to the inquiry and has chosen not to do so. The Brazil international denies wrongdoing.

West Ham will also be able to call upon Mohammed Kudus after the forward’s five-match ban. Lopetegui said the defender Jean-Clair Todibo was a doubt.