In 1984 – with the Bears starting 2–0 – Jim McMahon was injured and Mike Ditka inserted Avellini in as the starter for a road game against Green Bay. Avellini had only started five games since the end of the 1978 season. The Bears mustered little offense with Avellini at the controls, but still managed to edge the Packers 9–7. Chicago struggled the next week as they were soundly beaten by Seattle 38–9. This resulted in Avellini being cut from the Bears’ roster by Ditka, ending his decade-long tenure with Chicago. Avellini signed with the New York Jets in mid-November, where he ended his playing career after the 1984 season. The Bears, meanwhile, went to the NFC Championship game that season and won Super Bowl XX the next season. Avellini made a brief comeback in 1986 with the Dallas Cowboys, starting three preseason games, but was released as the final cut.