Chelsea boss AVB plans to integrate Cahill this week
He feels the centre-half will be fully integrated in the coming days.
"With Cahill, there are certain principles that take time to assimilate bearing in mind our defensive organisation. He had trained hard for four days and did extremely well," the Chelsea manager said.
"We decided for [Branislav] Ivanovic on the bench because he offers the possibility of right-back and centre-back, but I am sure Gary is going to be in contention for QPR."