Cardiff boss Malky Mackay feels his side's recent experience of a two-legged semi-final can give them a mental edge in the play-offs.
The Bluebirds secured their place in the top six with victory over Crystal Palace on Saturday and face the Hammers in Thursday's semi-final first leg at Cardiff City Stadium.
Palace were the opponents when Cardiff were attempting to reach the Carling Cup final earlier this season, with the Welsh club recovering from a 1-0 deficit after the first leg to eventually prevail on penalties and reach Wembley.
And Mackay believes that experience means his side have an inner strength to draw on against the Hammers, who narrowly missed out on automatic promotion to Southampton.
He said: "Going into a two-legged semi-final in a pressure situation is something we have had recently and there was an intensity about those semi-finals against Crystal Palace because of the prize at the end of the day, and this will be a very similar situation.
"Myself and some of the staff and the players have been through these situations before and to have it happen to us recently helps and gives us a strong mentality.
"We have been to the Carling Cup final and taken it all the way to penalties against Liverpool so there is a strength of character here at the moment that will enable us to handle a two-legged semi-final."