L.C. Greenwood and Earl Holmes Were part of the Steel Curtain along with "Mean" Joe Green and Dwight "Mad Dog" White. Together they helped the Steelers capture many victories. The Steel Curtain wasn't the only reason the Steelers defense was so good.  
Another part of the Steelers defense were the legendary linebackers Jack Ham and Jack Lambert. These two legends together helped make the unbeatable defense. Also Rod Woodson one of the leagues best cornerbacks helped the defense. All of this defensive talent helped the Steelers be such a great team. 
The Steelers offense was filled with great players in every position. With Terry Bradshaw throwing bullets to wide receivers like Lynn Swann who caught for 5,462  yards and 51 touchdowns in his 1974 through 1982 career. Players like this were unstoppable.
While the Steelers coach Chuck Noll was working on the offensive line to protect his quarterback, he found out his team needed a good running game. His problem was solved when he was noted "the ball clubs key man" by teammate "Mean" Joe Green. 
During that same time Return specialist and star cornerback Rod Woodson along with Rich Erenberg moved the ball downfield on the kickoffs and punt returns to give the Steelers great field positioning. The Steelers offense and defense has had many players admitted into the Football Hall Of Fame or is going to have many players. Either way the Steelers are always going to be a great team. 
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