The champions appear all but certain to relinquish their title after Angel Lafita's late equaliser handed Getafe a point at the Camp Nou on Saturday.
Atletico Madrid remain in pole position to win the league and their city rivals Real also look likely to finish above Barca, who are set to end the season with just the Supercopa de Espana to show for their efforts.
Martino believes his side have lacked consistency over the course of his debut season in charge.
"It hasn't been a good year, neither individually or collectively, because I was not able to make my intentions for the team reality and because we never showed Barca's best version," he said.
"It has been a difficult season with a lot of footballing issues.
"Of the three teams to fight for the league title, we were the least consistent.
"I don't think the players came into the final stretch of the season tired or fatigued, and I have no complaints with their commitment."
