"To blame the manager" means holding the person in charge responsible for something that went wrong or for the failure of a project or team. Full definition
I do nt blame our manager for this loss, he got his tactics spot on and a more clinical team may have this game wrap up by half time. (justarsenal.com)
You don't blame the manager, unless you can point to something specific he is doing wrong. (sbnation.com)
Some people blame managers for failing to look ahead and budget carefully, in particular, for failing to plan for the predictable end of federal stimulus funds. (educationnext.org)