The duo have entered the final six months of their existing agreements with speculation over their futures as they are now free to discuss terms with overseas clubs.
But Mustafi said: “Obviously, they are important – they are two big players. Alexis has been scoring a lot of goals, Mesut has been scoring and assisting a lot of goals so obviously they are very important because they are top class players.
“But the headlines, that is something really personal for them. They decide [their futures] with the manager so I don't care too much about it. The only thing we care about is when they are on the pitch, they give everything.
"That makes it for me, easier, because when I see the people in front give everything, it makes me want to give everything as well."