Complex sentence: They tied the Pittsburgh Steelers for first, and then defeated Pittsburgh in a playoff to reach the NFL championship game, which they lost to the Chicago Cardinals (led by All-NFL defensive back Marshall Goldberg), 28--21.
Split into simpler sentences: They tied the Pittsburgh Steelers for first, and then defeated Pittsburgh in a playoff to reach the NFL Championship game. In the championship, the Eagles lost to the Chicago Cardinals (led by All-NFL defensive back Marshall Goldberg) 28--21.