The Cowboys were coming off a disappointing 1974 season, after finishing with a record of 8–6, effectively ending an eight-year run of making the playoffs. Accompanied with the retirement or loss of key players like Bob Lilly, Bob Hayes, Cornell Green, Walt Garrison, Dave Manders, John Niland, and Calvin Hill, there was speculation in the media that the franchise was in decline.
For all of the accolades that the Cowboys' scouting department had received throughout the years, the team had never kept more than nine draft choices and the average number was keeping six. Their 1975 NFL Draft is considered to be one of the best in league history because twelve picks made the roster, hence the nickname "The Dirty Dozen". This rookie class, didn't even include linebackerMike Hegman, who was drafted that year but did not enter the NFL until 1976. Neither was included rookie undrafted free agentquarterbackJim Zorn who made the team, but was later cut to make room for running backPreston Pearson, who had been waived by the Pittsburgh Steelers.
The infusion of new talent not only provided an immediate rebuilding process, but also changed the course of the team in a significant way. This group helped the team reach Super Bowl X that season, and would play a key role in the Cowboys being given the name "America's Team".
The NFL didn't start recognizing quarterback sacks as an official stat until 1982; however, the Cowboys have their own records and according to their stats, Roger Staubach got sacked a league high 45 times the previous season and 43 the year before that, to revert this trend Tom Landry revived the Shotgun formation which he called "the spread", providing the NFL with another long lasting innovation.
The Cowboys experienced an unexpected success, winning the first 4 games on the way to a 10–4 regular season record. However, home losses to the 4–10 Green Bay Packers and 5–9 Kansas City Chiefs cost the Cowboys the NFC East championship. Had Dallas defeated both Green Bay and Kansas City, it would have held home-field advantage in the playoffs thanks to an 18–7 victory over the Rams in the season opener. On the other hand, the Cowboys made home field advantage moot with their playoff wins at Minnesota and Los Angeles.
The new look offense averaged 25 points per game and a revitalized defense that became known as "Doomsday II" gave up only 19 points per game.