The 26-year-old Argentina striker is back in training for the Blaugrana and could feature in their crucial trip to the Vicente Calderon next weekend
The three-time Ballon d'Or winner was back in training last week as he continued his recovery from a hamstring injury that has kept him out of action since November 10 and admitted he felt "great" to be back on the pitch.
However, the forward was left out of the squad that beat Elche 4-0 but, after the game, Martino admitted that the crunch tie at the Vicente Calderon may be the right time for the Argentina international to return.
"Messi has to recover from his injury then he could be able to play against Atletico,” Martino told reporters. "Not because they're our main rivals, but because it is time."
"He has trained well, and looks good physically and mentally.
"I haven’t decided on the team for the Copa del Rey game yet, let alone next weekend. We know what’s important is our shape.
"I can’t say for sure if we’ll rotate in the week, but I think it makes sense to try to peak towards the end of the season"
The Blaugrana coped well without the No.10 as they cruised past Elche on Sunday, thanks largely to an Alexis Sanchez hat-trick, and the 51-year-old could hardly fault any aspect of his side’s performance as they regained La Liga's top spot.
"It was good from us," he continued. "Apart from one occasion in the first half, we didn’t give them any options.
"We played well going forward and looked good in defence. I thought our second half performance was one of total control.
"We are having a good time at the moment. But there is still a lot we can do to improve – especially as we enter this part of the year."