With budget's tight he needs players to be adaptable.
"We've used Danny Jackman and Jason Crowe in central midfield and they're both full-backs by nature but I don't think it hurts any player to play them in several positions," Gray told the Northampton Chronicle.
"If I asked Chris Doig or Gabor Gyepes to go and play up front then I'm sure they would do.
"The 10 outfield players should all be interchangeable. I always look at Brazil, I think their outfield players must all have started as centre-forwards because they all want to get forward and they all look so confident on the ball.
"I don't think players can pigeon-hole themselves in one position. They all want to play, that's the be-all and end-all of it."