The Argentine coach hailed the 26-year-old's display on Wednesday night and feels the Catalans are obligated to win their group after a 3-1 win over rivals AC Milan
The Argentina international netted a double at Camp Nou to help his side claim all the three points, sealing qualification for the knockout stages in the process.
And, with Messi struggling to find his best form in recent weeks, Martino was delighted with his compatriot's return to form.
"Making negative assertions about Leo has risks. He played phenomenally well today," the Barca coach said at the post-match press conference.
Martino then went on to voice his satisfaction with the Blaugrana's qualification for the knockout stages and stressed that they must now secure top spot in Group H.
"Because there are no real surprises in the groups, you can assume that the favourites will get through but you never know who you will draw in the next round. We wanted to get out of the group early in order to feel better.
"Qualifying on matchday four means the pressure is off but we still have an obligation to finish first in the group."
Barcelona take on Ajax during matchday five, before finishing the group stages with a home game against Celtic.