Zenit St Petersburg boss Roberto Mancini is being linked with West Ham.
The London Evening Standard says the Italian is second favourite behind Newcastle manager Rafa Benitez if West Ham decide to make a change.
Slaven Bilic is under increasing pressure following three successive Premier League defeats - all away from home while the London Stadium is re-configured following the World Athletics Championships - and another loss, against Huddersfield in a week's time, would only increase the speculation.
Benitez is said to be unhappy about Newcastle's failure to land his chosen targets during the transfer window and West Ham would need to pay £5million compensation to land him.
Mancini was linked with West Ham last season, when Bilic found himself under pressure following a run of poor results, and the Italian was spotted at a West Ham match.
West Ham decided then to persevere with Bilic and could do so again if their results improve.