it's not just defensive errors dude, we really lacked character and willingness in many games. Like against spurs, I thought we played better than they did most of the game. It was easy balls missed by Maxi and Torres that game. It doesn't mean that our backline is perfect, it's for sure needs much work. At least, when I compare these games to Rafa's games, we have our midfielders back the defenders now. They do it better than Rafa's era. I do agree with CP1972, too. We possess the ball less.
When we watch all games this season, almost all goals or dangerous chances for other teams came from back sides. In depth, we sometimes do well and some others we're so open. If we wanna repair our back line: we should possess ball more, we should have our midfielders back so fast with a better bonding with defenders, and we shouldn't miss easy balls to score. It's more tactical work than players. Though, I'm not pleased most of the games.