Whilst i don't blamee him directly, I don't think Pellegrini is completely blameless here. I get that this was an important game and you want your captain playing when possible and i know that injury could of happened at any time in any game and i also recognise hindsight is a wonderful thing but everybody I spoke to pre-match was in agreement that we should of rested some of our key players, notably Kun Silva and Kompany and how it will probably come back to bite us. A guy that's been plagued with injuries all season played 6 games in 20 days, we had all 4 centre backs fit, and took a 3-1 lead into the game there couldn't of been a better time to rest him and others than last night.
In all likelihood, playing 6 games in 20 days probably didn't contribute to his injury directly but to play him every game bar Chelsea since his return is bad management in my eyes. He should of been afforded a game or two on the bench, especially when 2 of those games were against the bottom 2 sides in the league.
Pellegrini isn't directly to blame for the injury but playing him as frequently as he did since his return is just yet another example of poor management from our wonderfully charming manager.