David Moyes questioned the officiating at Selhurst Park after his side were defeated by Crystal Palace on Saturday.
West Ham struck first through Tomas Soucek, but Roy Hodgson's revitalised side struck back with three first-half goals courtesy of Jordan Ayew, Wilfried Zaha, and Jeffrey Schlupp.
After entering the interval with just a one-goal deficit to chase after Michail Antonio headed home from a corner, Palace would again double their advantage after Eberechi Eze was ruled to have been fouled inside the box.
Eze then converted the penalty after the referee pointed to the spot, but after the game expressed his discontent with the Craig Pawson's decision.
'I think the referees said they wouldn't give soft penalties, I think today could certainly be classed as one of them,' Moyes told BBC Match of the Day.
Moyes' side later netted again from a set piece, this time thanks to a header from Nayef Aguerd amidst a goalmouth scramble, but were unable to find an equaliser.
Speaking on his side's defensive fragilities, the West Ham boss admitted that he felt that his team had ultimately gotten what they deserved out of the game.
'We didn't start the game particularly well, could have been the quick turnaround and having a day less than Crystal Palace to prepare. We scored and gave ourselves something to build on,' Moyes added.
'We scored good goals from set pieces but overall we got what we deserved but I do expect our teams to defend better than that and over the years we have done. Today I was really disappointed with how we defended.'
A second consecutive Premier League defeat sees the Hammers just five points from safety with five games remaining.
However, Moyes indicated that he remains confident that his team will be able to survive the drop.
'We're not over the line yet, we have to do that and try and get the points which are required.
'I always thought the programme would be difficult today, the extra day recovery gave them an advantage, the early kick off certainly didn't help but look we're all in it and we have to do it and find the points which will get us there and I'm confident we will do.'
