Fati wakes up his team with the only shot on goal by Quique Setién's team in the first half (min. 42). The young forward once again proved his worth with a goal to open the scoring and keep his team at the top of the league.
Five changes to refresh his team (Lenglet, Junior Firpo, Rakitic, Arthur, and Ansu Fati), but there were many minutes without football for Quique Setién's team. Predictable, without rhythm, undermining the good sensations offered in Mallorca on the return of LaLiga.
Barça's lack of control was evident against a rival that put up a line of five, another of four, and Guerrero up front to try to stop the blaugrana and with very little, very little, was able to give them more than one scare.
Leganés relied everything on defense, but found two chances to break the game. Then, as it almost always happens, if you forgive, you pay, and that's what happened.
Without continuity, playing almost in slow motion, without breakthroughs, and with a flat style of play, Barça didn't react even to the two clear chances that Aguirre's team had before the quarter-hour mark.
In the first (minute 12), an attacking action by the blaugrana ended with a great transition by the 'pepineros', a drive by Eraso, and a shot by Guerrero that Lenglet prevented from going in when Ter Stegen was already beaten.
Guerrero, two minutes later, had another one, although this time he was too far out and his shot at the far post didn't find the net.
Barça didn't know how to counteract Leganés' style of play. On the sidelines, Quique Setién was getting desperate: "You're taking too many risks with the ball," he warned Arthur after yet another loss, because one of the few good things about football without an audience is that you can hear everything: the coaches' comments, the players', and even the ball being struck.
Barça's first shot, although it didn't hit the target, was a header by Griezmann that went wide after half an hour. Bustinza kept Messi under control and the Argentine started to increasingly seek the sidelines due to the density in the center.
But the chances didn't come. Barça got tangled up in the Leganés' web and only on the left, with Firpo and Fati, did they pose any danger.
In an isolated action, Junior Firpo fought inside the Madrid side's area and the ball bounced out. Ansu Fati caught it, controlled it, and shot in the 42nd minute. 'Pichu' Cuéllar only saw the ball go past him into his goal in Barça's first shot of the game (1-0).
In the second half, Aguirre added an extra striker (Assale) for Roque Mesa and in a controversial decision, Quique Setién brought in Luis Suárez for Ansu Fati, the only forward until then capable of revolutionizing the blaugrana's game.
The game livened up after a goal disallowed for Griezmann in the best play of the match. Messi gifted him a through pass, Semedo then passed it to the Frenchman, who beat Cuéllar in the 64th minute. VAR review determined that the Portuguese was offside.
That play woke Messi up and in the next action, in the 67th minute, the Argentine forced a penalty that he himself scored to seal the game (2-0) and score his twenty-first goal in LaLiga.
Arturo Vidal, Umtiti, and Riqui Puig later came on; Leganés had long ceased to believe, but Barça had already shifted gears and had their minds on the next commitment, in Sevilla's complicated field, where they will arrive as the sole leaders.
Technical information
2 - FC Barcelona: Ter Stegen; Sergi Roberto (Semedo, min. 54), Piqué (Umtiti, min. 73), Lenglet, Junior; Busquets (Arturo Vidal, min. 63), Rakitic, Arthur (Riqui Puig, min. 73); Messi, Ansu Fati (Suárez, min.54), and Griezmann.
0 - Leganés: Cuéllar; Tarín, Bustinza, Awaziem; Silva (Kevin Rodrigues, min.71), Recio (Bryan Gil, min. 85), Rubén Pérez, Roque Mesa (Assalé, min. 46), Aitor Rubial, Eraso (Ibrahim Amadou, min. 63); and Guerrero (Carrillo, min. 71).
Goals: 1-0, min.42: Ansu Fati. 2-0, min.69: Messi, penalty.
Referee: Juan Martínez Munuera (Valencian Committee). Showed yellow cards to Bustinza (min. 37), Rubén Pérez (min. 67), Awaziem (min. 82), Umtiti (min. 83), who will miss the next match due to accumulation of yellow cards, Riqui Puig (min. 84), Lenglet (min. 84), Junior (min. 89), and Rakitic (min. 90+3). Expelled Javier Aguirre in the 95th minute.
Incidents: Match of the twenty-ninth matchday of LaLiga played behind closed doors at the Camp Nou.