The 22-year old German midfielder was involved in a collision with a lorry near Hoffenheim's training ground and was airlifted to hospital with serious head injuries.
Vukcevic is in a critical condition in a Heidelberg clinic after undergoing surgery and the club is closely monitoring his situation.
"This news has shaken us," said Hoffenheim's general manager Andreas Muller.
"The team, the coach and everybody here are shocked.
"Our thoughts are with Boris and his family."