The Argentine coach has paid tribute to his compatriot for earning the Blaugrana three precious points with a coolly-taken penalty in the Catalan derby
The Blaugrana looked set to squander the opportunity to overhaul Atletico Madrid at the top of La Liga but their talismanic No.10 coolly converted from a penalty with just 13 minutes to go to send the reigning champions two points clear.
"With Messi on the pitch the story almost always ends the same way," Martino told reporters.
"Winning here is important because it was a derby. You always have to win these matches, so we value the victory very much.
"All of the remaining games are very difficult. They are seven cup finals."
Martino's sentiments were echoed by centre-half Javier Mascherano, who feels that Barca cannot afford to drop a single point between now and the end of the season if they are to hold onto their title.
"I know full well that we have picked up three valuable points," the Argentine added. "It was a derby. We know that they're never easy.
"In addition, Espanyol are a team that makes you play at full strength, as they always play well against the big teams.
"At this stage of the season, a derby win only makes us stronger. But it does not change anything: we have got seven games left and to be champions we will have to win them all.
"But every game is different. We have to go one game at a time."
Meanwhile, Martino took time out to send a message of support to goalkeeper Victor Valdes, who saw his season ended by injury in midweek.
"We dedicate this win to him," he stated. "This team is accustomed to bad news and how they choose to respond is to work hard in the field."