A driver who has admitted fleeing after hitting a teenage cyclist at a Coburg juction in a collision that left some of the girl's hair in the car's windscreen and the 13-year-old fighting for her life, has failed in a bid to be sentenced by a lower court.

Thi Nguyen, 41, pleaded guilty after failing to stop and render assistance in November after she hit the young cyclist with her BMW near the corner of Bell and Sussex streets.

Thi Hang Nguyen in November after she was charged over the hit-run. Credit:Jason South

The child was placed in an induced coma with life-threatening internal injuries and a fractured rib.

If the matter had been dealt with by Melbourne Magistrates Court, the Sunshine woman would have received a lighter sentence such as a fine of several hundred dollars, a community corrections order or a maximum 14-day stint in jail.