The footballer, who many believe is the favourite to win a fifth consecutive Balon D'Or award this season, cut a slightly dejected figure in his side's 1-0 win at home to Espanyol Friday night, Xinhua reported.
It was his fourth game without hitting the back of the net for Barca, the first time since 2011 he has gone four matches without scoring.
He is the most important player in a team of stars: Coach
Messi has suffered a series of muscle injuries since April with the last of those just before the international break and he admitted in a release on his Weibo, China's twitter like social website, that he is still not fully recovered.
"Games against Espanyol are always very complicated. Physically I am still not at 100 percent, but I am sure that with more games I will get the rhythm," said Messi.
What is worrying for the club is that on several occasions against Espanyol as against Real Madrid and Celta Vigo in previous matches, Messi lost out in a sprint for the ball to rival defenders.
That has led club medical staff to think that although his muscle problem has cured, the striker has a crisis of confidence as he is worried about risking another torn muscle and as a result he is involuntarily slightly holding back when he runs for the ball.
However, it is also clear that as Messi says, the solution is not that the player sits games out on the sidelines, but that he plays games with the aims of recovering his confidence.
When asked about whether or not he was worried about his striker after the Espanyol game, Barca coach Tata Martino was clear with his words.
"He is the most important player in a team of stars, he plays and he offers us everything. I don't see him looking worried and what is happening at the moment is pure coincidence. I don't see him looking desperate, he shot with intent but without fortune and he has set the bar so high in the past that sometimes it is hard to beat that," Martino commented.
There was good news for Barcelona Sunday regarding left back Adriano. The Brazilian limped out of Barca's win away to Celta Vigo Tuesday night and sat out the game in the Camp Nou Friday.
However, he was able to train on Sunday morning and should be available to start in this week's Champions League clash at home to AC Milan.
Meanwhile Javier Mascherano, who had to be substituted late in Friday's game should also be able to play in the game where a win would assure Barca's place in the knockout stage of the competition.