Martinez was just recalled on Aug. 7 and said he understood the move.
"They had to make a move," Martinez said. "I know I'll be back soon in like two weeks."
Martinez's playing time was limited behind outfielders Carlos Beltran, Angel Pagan and Jeff Francoeur. Manager Jerry Manuel said Martinez needs to work on a few things with his swing.
"The approach that he had is one that doesn't really recognize offspeed pitches," Manuel said. "If you don't recognize offspeed pitches, then you have to guess with that. He's done a good job to survive with what he's doing in guessing what is what."