Martinez denied progression would be to the detriment of their bid to stay in the top flight.
He said: "We have always said that if we want to be successful in any competition it is not about having 12 or 13 players but having 22 or 23 and having a stream developing with our youngsters.
"In the FA Cup we are now a team who can make nine or 10 changes and still have a team who know what they are doing with real good unity. We face every competition wanting to go as far as we can without depleting ourselves for the league.
"It was a difficult game for the referee today as there was a lot of action in both boxes and you expect that in cup competitions. There was a lot of physicality and it was a typical, typical cup game."