Come on Alarcon, be reasonable. Players playing like shit is Martino's fault? Really man? The players are just not that good anymore and/or have very poor form. Look at the team up and down.
Pique - Never was World Class. For years he was shielded by a strong midfield, and some great partners in defense. Now that he is The Man in the backline, his deficiencies show. He is just a decent defender.
Mascherano - Never a CB. Good player, not a CB.
Bartra - Young, inexperienced, physically weak.
Puyol - Done
Alves - Decline
Adriano - sub type player
Alba - poor defender, lots of injuries this season, poor form.
Montoya - average player
Busquets - Bad form. Very very poor season so far.
Song - Not good enough
Xavi - Decline. Not fit to play consecutive games.
Iniesta - Bad form at the start. His form has improved a lot, but he's missed some games too.
Cesc - Good season, but he is a mercurial player. Great performances one day, bad ones the next.
Roberto - As vanillas as it gets.
Tello - Technically inept, not Barca quality.
Pedro - up and down.
Alexis - good season, but not a dependable scorer. He is much more a support player.
Neymar - up and down.
Messi - injured, recovering form.
What is Martino supposed to do? Any manager out there would struggle with this team. This is not Barca 2010-2011. Not even close.
I'm almost certain if Pep got this team now, he'd unload about half the team for new players.
EDIT: I should clarify. When I say struggle with this team, I mean struggle to keep this team as the top team in the World. The team is still actually a good team, however not good enough to be above and beyond the rest. Any manager would struggle with this team if the goal were to be the best in the World. The players are just not there for that.