depends on the kind of goal though tbh
goalkeeper is usually the last to blame unless it's a really easy save
always the defenders. however, in some cases, the keeper is to blame too
when someone scores. is it because the player who scored did a good job. or the goalkeeper did an awful job?
mostly a goal is the whole team's fault for not doing their job properly unless the goalie let's in something completely ridiculous, then it's his fault. But I'd say it's defenders fault for letting such an opportunity arise in the first place. (I'm a former goalie so I'm definitely not biased :)