Michail Antonio was sent off as West Ham stretched their unbeaten Premier League start to four matches with a goalless draw at Southampton, who remain without a league win this season.
Antonio was shown a second yellow card for a rash challenge on Moussa Djenepo in second-half stoppage time.
Chelsea loanee Armando Broja had gone closest to snatching all three points for Saints late on, striking the foot of the post with a low effort before having a late header cleared off the line by West Ham captain Declan Rice.
West Ham enjoyed the majority of possession but failed to force a save out of Alex McCarthy until the early stages of the second half, when Antonio’s low drive was held by the Southampton keeper.
David Moyes’ side looked the more likely winners as the second half progressed and almost broke the deadlock through Jarrod Bowen, whose sweetly-struck volley was tipped over the crossbar by McCarthy after Southampton had failed to clear Vladimir Coufal’s low cross.
West Ham have avoided defeat in their opening four Premier League matches for only the second time, having last done so under Harry Redknapp in 1999.