I think you'll find you're the one making things up.I guess we must have watched different games, because the events you describe seem to be entirely fictitious. The second goal where he stood off and then stood in treacle running back? He stood off because he had a man on his shoulder that he had to track. Then when the guy got within shooting distance he closed him down and blocked the shot, then got back in position to cut out the ball to the far post, but the ball never went anywhere near him as it was met by the man at the near post, where Otamendi would have been if he hadn't decided to charge across and lunge at the shot, completely taking himself out of the game.
As for the first one your description bears absolutely no resemblance to what actually happened. You've made up some lovely little back story to explain him being out of position, which he wasn't, then claimed that Otamendi stepped up, which he didn't. The reality is that they played a one two down the left in behind Kolarov, which would have been 2 yards offside, but Otamendi and Clichy were giving their brains a little rest on the near side, just standing around playing him onside and also not covering across into the middle like they were supposed to.
Obviously this is pointless as you've already made up your mind about Mangala, so will see whatever you want to see to justify it.
Not one thing I said is untrue or didn't happen. Your allegience to all things from the Portuguese league is blinding you to factual events.
I mean, to say Otamendi didn't step up on the occassion to try and play offside is baffling.