West Ham boss Manuel Pellegrini admits his side need to overcome a mental block to address their worrying form on the road.
The Hammers were beaten 2-0 by Premier League strugglers Cardiff on Saturday, a result which leaves them ninth in the table.
Pellegrini's side have now lost five of their last six league games away from home without scoring.
"It may be getting in the heads of the players," Pellegrini said of the away form.
"I was surprised the way we played. I kept the starting XI that played so well against Newcastle and we spoke so much in the week about facing a team who is fighting against relegation.
"They were beaten badly here in their last two games but we couldn't match what they did.
"They started very quickly and scored an easy goal. It's difficult to find the reason, we knew it would be difficult."
West Ham return to action against the league’s bottom side Huddersfield next Saturday.
