The Bears opened their 1984 training camp in a new location, Platteville, Wisconsin as head coach Mike Ditka needed his team to get away from any distractions they might face at home. The team was on the verge of discovering a group of young leaders for the first time, and began to show the dominating defense that would emerge in full the following season, and pushed much farther than anyone expected them to go.
Chicago opened the season by routing the Tampa Bay Buccaneers, 34–14. In Week Two, they shut out the Denver Broncos 27–0 behind a huge day from star running backWalter Payton. This game featured a famous image from Payton's career: a 50+ yard run down the sideline, led by 2nd-year guard Mark Bortz, an 8th round draft pick that was converted from defensive tackle.
In Week Four, the Bears' lack of offensive power was evident as they lost to the Seattle Seahawks 38–9. After this loss, Ditka cut Avellini. The following week, the Bears lost to the Dallas Cowboys 23–14, bringing their record to 3–2.
On October 7, 1984, Walter Payton reached a major milestone as he surpassed Jim Brown as the game's all-time leading rusher in yards, he did it in the third quarter of a Week Six home game against the New Orleans Saints. The Bears beat the Saints 20–7. Incidentally, the 1984 Bears ran for the second-most rushing attempts in a season, with 674.
In Week Seven, the Bears lost 38–21 to the Cardinals in St. Louis the following week. Sitting at 4–3, the Bears proceeded to win three in a row. They beat Tampa Bay 44–9, then Minnesota Vikings at home, 16–7. Following the Minnesota win came the biggest challenge for the Bears: a showdown with the defending world champion Los Angeles Raiders. The Bears beat the Raiders 17–6, a game that showcased Richard Dent, who collected three against Raiders QB Marc Wilson. (Dent would finish with 17.5 sacks, third-most for the season behind Mark Gastineau and Andre Tippett. The Bears would then record 72 sacks, a team record. The Bears' victory was marred by a kidney laceration suffered by Jim McMahon, ending his season.
Six-year veteran QB Steve Fuller had been acquired from the Los Angeles Rams prior to the 1984 season for insurance in case McMahon was injured. The investment paid off, as Fuller guided the Bears to a 2–1 record over the next 3 games. In the third game at Minnesota's new Hubert H. Humphrey Metrodome in Week Thirteen, the team clinched its first NFC Central Division title.
After the Minnesota game, Fuller was injured, and Chicago was faced with another quarterback problem. Ineffective Rusty Lisch replaced the injured Fuller and lost the Week Fourteen game at San Diego, then started the following week against Green Bay at home. Lisch was again ineffective, so Ditka inserted none other than Walter Payton behind center in the shotgun formation. Payton, unsurprisingly, was ineffective as well, and the Bears lost to the Packers 20–14.
Fuller was expected to return by the playoffs, but Ditka didn't want to enter the postseason with another loss. The Bears signed 14-year journeyman Greg Landry to start his last NFL game against his previous team, the Detroit Lions, in the season finale. The Bears won 30–13, and were headed to the playoffs for the first time since 1979.
The first-round matchup sent the 10–6 Bears to Washington, a team that had lost to the Los Angeles Raiders in Super Bowl XVIII. Washington was heavily favored, but Chicago came away with a 23–19 victory that featured touchdown passes from Fuller, as well as Payton on a halfback option pass.
With the momentum of defeating the defending NFC champions, the Bears then travelled to San Francisco for their first appearance in a championship game of any sort since their championship year in 1963. The line for the game came down steadily as the week wore on, but the Bears were shut out 23–0. Fuller had performed poorly in games against tough opponents, and the offense sputtered as the 49ers were able to render Walter Payton ineffective. The team had gone farther than many had expected them to go in 1984, and the season set the stage for their Super Bowl winning 1985 season.