Messi has been missing from action with a thigh injury sustained in Barcelona's 4-1 triumph over Real Betis in November, but Martino has revealed in a press conference that Messi is nearing full fitness and looks hungry to return.
"He's come back really well and he's had three good training sessions. He has the look of a killer," said Martino.
"He's lacking the rhythm of training with his team-mates, but he's done more work with the ball.
"We are looking at when he will be ready to play."
Messi is due to return for Barca in January and the Argentina captain has targeted an injury-free 2014.