The energetic midfielder was an integral part to the Blues’ success last season and therefore his absence has been one of the main causes for disappointment during this campaign.
The former Wigan man has been hampered with a persistent hamstring injury and has only played seven times since the start of November but McCarthy returned to training in Qatar this week.
Martinez revealed that Sylvain Distin also joined the squad in warm weather training and is closing in on a return after suffering a groin injury.
Martinez was quoted on the club’s website as saying, "Sylvain Distin and James McCarthy are really progressing a lot in this warm weather and that's really positive news."
"They have both joined the group in training and have come through really well.
"I see James as being fully fit now but we will assess everybody before the Crystal Palace game.
"This week has allowed James to build up his fitness levels and I do expect him to be fully fit and ready for Crystal Palace."