The problem with backup GK is that it's almost an impossible position to get "right". Either the person filling the role is squarely back-up caliber, which means they aren't good (or else they would've found somewhere to start), or they're overqualified to be a backup GK and they won't be satisfied with potentially never playing during the season aside from the rare Coppa game. In a sense, late stage Handanovic is someone who actually does fit the role because you can talk yourself into believing that a former GK great might no longer be consistently good, but on a here-and-there basis maybe you can still get quality from them. (Of course, there's also players who need to play consistently to find form as opposed to being here-and-there players, so this logic is anything but infallible.) But someone like Di Gregorio? He's been starting all season for a comfortably mid-table team that might be able to compete for a European spot. It doesn't make sense for him to take a step back to being a backup 'keeper, even if it's for only one season.