Garcia Pimienta's team turned a 0-2 scoreline around and ended up winning to stay near the top of the league
The first few minutes of the game belonged to Llagostera. Gil Muntadas went close, whilst at the other end Collado was out of luck with a low shot. On 15, Balde couldn't continue and was replaced by Roger Riera, an unexpected early change for Garcia Pimienta.
The visitors soon took the lead from a penalty in the 19th minute, Sergio Cortés the scorer. Despite playing on the front foot, Barça were pegged back further on 34, as Gil Muntadas found the net from outside the box.
It required a response and it got one, Rei Manaj's brilliant individual effort on 41 halving the deficit.
The second half started very well for Barça B, and Konrad added a quick fire second just three minutes into the second half.
Lucas de Vega added a third nine minutes later, and with the hosts in the ascendancy, Collado's magnificent dribble into the box got the finish it deserved on 66.
The result leaves the Catalans third in the table, tied on 29 points with Andorra, who have played one more game.
Barça B, 4 Llagostera, 2
Barça B: Carevic, Comas, Mika, L. De Vega, Collado, Konrad, Matheus (Jandro, min 45), Álvaro Sanz (O. Busquets, min 85), Nico (Ramos Mingo, min 85), R. Manaj (Zeballos, min 79) and Balde (Roger Riera, min 15).
Llagostera: Marcos, Bigas, Monreal, Cortes, Sascha, Gil, Diego, Pere (Aimar Moratalla, min 60), Manchon (Juvanteny, min 79), Guiu (Salvans, min 60) and Duba (Christian Dieste, min 60).
Goals: 0-1, Cortés (min 19); 0-2, Gil Muntadas (min 34); 1-2, Rei Manaj (min 41); 2-2, Konrad (min 48); 3-2, Lucas de Vega (min 57); Collado (min 66).
Official: Martínez García. Yellow cards for Matheus, Álvaro Sanz, Nico, Manaj and Konrad