West Ham’s shock win against Chelsea last month was masterminded by Enzo Maresca, with the club’s second assistant coach taking over training from Manuel Pellegrini in the lead-up to the game.

Pellegrini normally devises West Ham’s tactics and the manager is likely to be sacked if his team are beaten for the eighth time in 10 matches when they visit Southampton on Saturday. West Ham are a point above the bottom three following the defeat against Arsenal and patience is wearing thin at board level.

West Ham's Pellegrini stays for now but Southampton defeat could bring sack Read more

Pellegrini bought himself some time when West Ham, who will fall below Southampton if they lose at St Mary’s, beat Chelsea 1-0 at Stamford Bridge. But it is understood that the tactics were devised by Maresca, who could be asked to step in on an interim basis if West Ham lose against Southampton.

West Ham knew that Chelsea wanted to play through the middle, so they pushed them wide and gave few chances away. However Pellegrini then resumed control, restoring his style for the limp defeats against Wolves and Arsenal.

Play Video 1:02 'We need the results': Manuel Pellegrini feeling the pressure ahead of Southampton – video

There is alarm at West Ham, who have been dragged into a relegation battle following a dramatic loss of form. It is understood some senior players are losing faith in Pellegrini, who has 18 months left on a contract worth £7m a year. West Ham’s board have a history of backing their managers but their hand could be forced if there is no sign of an improvement against Southampton.

Maresca, who joined Pellegrini’s coaching staff in the summer of 2018, is building a good reputation within the club. The former Juventus and Sevilla midfielder is respected by the players, who have made clear to senior club figures that they have enjoyed his training sessions. Maresca played for Pellegrini at Málaga.

West Ham’s shortlist includes David Moyes, Chris Hughton and Eddie Howe, who could be reluctant to leave Bournemouth before the end of the season. There is also admiration for Simone Inzaghi, though it is unlikely he could be tempted away from Lazio, who are third in Serie A.