Messi has not played since picking up a hamstring injury in his side's win away to Betis Nov 10 last year, Xinhua reported on Saturday.
Given the striker had suffered a series of muscle injuries during 2013 and seemed to have had his confidence affected by the run of bad luck, the club decided not to rush his comeback, which was completed in Argentina.
Messi returned to Barcelona this week.
Although Martino did not say whether or not Messi would take part in Sunday's home game against Elche, he made it clear he is content with the striker's recovery.
"I see him with a killer's look in his eyes," said the coach.
"Sometimes you want things to be better than they are, but my feeling is that Leo has come back very quickly and he is in great physical shape and he has carried out three excellent training sessions with his team-mates," he added.
However, there was one factor that still worries the Barcelona coach: the fact Messi has not played a competitive game for almost two months.
"He is still lacking the rhythm of his companions, but he is in good shape and his return depends on how he feels," said Martino.
That almost certainly means Messi won't start against Elche, but he could form part of the squad and have some time as a second half substitute, otherwise he may have to wait until the midweek Copa del Rey tie at home to Getafe before making his comeback.