It would have been the 40th birthday of Three Rivers Stadium earlier this week, and what better of a tribute than showing a live NFL game from its friendly confines between two of the best teams from the 1970s?

Through the magic of the interwebs, our crack team of research aces uncovered this gem of a YouTube clip, showing, in its entirety (campy, overdone 70s commercials and all), the first half of the Steelers' 23-10 win over the Vikings on Nov. 26, 1972.

This is just awesome...in so many ways.

1972-11-26 Vikings vs Steelers 1st Half (via onthegridiron)

And here's the second half.

1972-11-26 Vikings vs Steelers 2nd Half (via onthegridiron)

Some points of note:

• Mean Joe Greene...unstoppable. Find a play where the Vikings offense manages to stop the Hall of Fame defensive tackle. I didn't see one. Double and sometimes triple teams fail to even slow him down. He wreaks havoc along the line like no one else.
• The lack of TV timeouts. Notice how fast the game moves? After possession changes, each team runs its players out on the field as if it's a hurry-up offense.
• At 27:37 of the first half, the broadcaster mentions Buffalo looking to score an upset over Cleveland (snicker), after the Bills go up 10-0 after a touchdown run by O.J. Simpson.
• No sideline reporters. The flow of the game is just allowed to breathe. No stupid music or graphics pumped between plays.
• Watch the goal line stand at 29:50. Ball gets snapped, the Steelers defensive line in unison moves the offensive line backward. Jack Ham makes a big play, but this is as fine an example of a defensive team stop as opposed to one player you'll ever see.
• The Firestone tires commercial at 31:24..."A girl can't always just get out and push." High comedy. Could you imagine what would happen today if a commercial suggested something like that?