Hummels is fully fit to play the final according to reports based on training session.
Without the ball it will come down to Mats-Bastian-Khedira focusing on Messi and someone constantly harassing Mascherano. Sorry but there is no scenario in which Argentina wins besides extreme luck, one Messi magic trick won't suffice, you'd have to convert the couple of half-chances and set pieces. Also I see posters conveniently ignoring the performance against France who showed earlier how lethal their counter attacks are, and somehow try to downplay the mighty Spain of 2010 for some reason. Yes Brazil collapsed but at the same time the way the players took advantage of the space was master class, any other team would have taken shots at an earlier stage of the attack and probably missed, instead the Germans ruthlessly reduced the chances to simple tap ins. Don't forget that nobody has really pushed the team to the brink besides Ghana, Löw immediately responded with subs, created plenty of chances and equalized. At this stage energy conservation was the priority. Anyway that's my analysis.