Giroud has already been an important part of Milan for a long time. He played a really critical role in some of their games so far as well. His World Cup performance is also very valuable because this is helping him become a more valuable player on one hand. He is getting quite old maybe but the quality is still staying the same.
I think he is already a serious candidate for Milan's starting eleven in the rest of the season. I mean of course they give him chances but he should be getting more playing time thanks to this very impressive effort.