The four-time World Player of the Year hasn't played since tearing his hamstring in Barca's 4-1 win over Real Betis on November 10.

After beginning his treatment for the injury in Barcelona, Messi then returned to his native Argentina to continue his recovery process during December.

However, he returned to Barcelona last week to begin training with his teammates once more and Martino admitted it had been difficult to leave him out of Saturday's 4-0 win over Elche.

"I have spoken with him and he is in the squad," Martino told a press conference on Tuesday.

"We are happy for him and I am especially happy to have all the players available.

"There was a lot of pressure for him to play against Elche, that would have been the normal thing to do. However, the difference now is that he has had more training sessions with the team.

"Tomorrow we will see if he plays from the start or not."

The news comes also as a huge boost for Martino's men as they travel to face Atletico Madrid in a top of the table clash in La Liga on Saturday.

Both sides are locked on 49 points after 18 games having dropped just five points each so far this season.