An advancement system for an in ovo injection apparatus is provided. Such an advancement system is configured to advance an egg carrier carrying a plurality of avian eggs to an injection assembly. The advancement system includes a guide assembly configured to receive the egg carrier and provide support thereto during advancement of the egg carrier. A manual advancement device slidingly engages the guide assembly such that the manual advancement device is movable along the guide assembly. The manual advancement device is capable of interacting with a trailing end of the egg carrier to advance the egg carrier to an injection position. At least one stop is positioned to interact with the manual advancement device during advancement of the egg carrier so as to prevent progression of the manual advancement device beneath the injection assembly, thereby locating the egg carrier at the injection position. An associated method is also provided.
