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Whenever fans in the Steel City reflect on the great tradition of Pittsburgh Steelers football, they're among an elite class. After all, few teams in the NFL have given their loyal followers so many memories, wonderful wins and timeless moments.

The A-list for most would include the Immaculate Reception, Santonio Holmes' fingertip catch and toe-tapping touchdown in Super Bowl XLIII, Lambert lambasting Cliff Harris and Harbaugh's heart-wrenching Hail Mary attempt at Three Rivers among others.

One of the proudest moments for the Black and Gold came in an era that isn't remembered as dominant for the City of Champions. In fact, on October 14, 1984, Pittsburgh traveled to Candlestick Park as a shell of the dynasty that had won its fourth Lombardi Trophy less than five years earlier. Lost in the mix of great moments in Pittsburgh sports history, the contest literally may have changed NFL history against all odds.

In today's game, deep undefeated stretches seem common. Teams finish anywhere from 14-2 to the once unthinkable 16-0, at least one team vying for an undefeated campaign late into December almost annually. In 2009, both the Saints and Colts (who are 0-13 in 2011, ironically) didn't lose until the final month.

Despite some great teams' best efforts, only one team has still accomplished the goal of winning every game. Unlike today, teams didn't go deep into December unblemished in the 80s. The 1985 Bears, who traveled to Miami with a 13-0 record, were rarities. San Francisco could have easily joined the fraternity, if not finished undefeated, if not for Pittsburgh.

The 49ers, eventual champions, would end Super Bowl Sunday with an 18-1 mark. Their only blemish came against the Men of Steel. The emotionally charged contest is an accomplishment not recalled nearly often enough in western Pennsylvania.

Making Pittsburgh's disruption of history more impressive was the quality of the opponent.

The San Francisco 49ers were revolutionizing the passing game. The West Coast offense has become a fancy part of football lingo when Bill Walsh adopted the philosophy from his coordinating days with the Cincinnati Bengals. Refining the offensive system, Walsh implanted the perfect quarterback to exact his vision with Joe Montana.

Crisp, efficient passes riddled defenses. While many labeled the approach as a "short" passing game, an observation stemming from the concept of "long handoffs" or "using the pass to 'run' the ball," Montana's passes were seamless beams that found various targets everywhere on the field.

Few teams could boast the 49ers' average yards per pass attempt (8.2 YPA). And, frankly, no team could beat a defense in more ways than San Francisco, whose moving pocket and array of attack options made them completely unpredictable and often indefensible.

Many fans associate Jerry Rice and John Taylor's heroics with the San Francisco dynasty, but the offensive weapons on their earlier champions included neither All-Pro. Dwight Clark became a legend in making "The Catch" against the Cowboys a few years earlier en route to the championship, and other playmakers included Earl Cooper, Russell Francis and Wendell Taylor.

While they may have been remembered for Montana's ability to make the aerial passing game seem artistic, the 49ers had great balance on offense, running more often than passing at a nearly even ratio. With 4.6 yards per rush, both elements of the West Coast were working in machine-like precision.

The defense for the pride of California also had a champion's pedigree. The secondary was stout, with Ronnie Lott making like a Mel Blount for the 80s, alongside other defensive stars such as Erik Wright and Fred Dean . The unit had 51 sacks and 25 interceptions, assuring that if their high-powered offense could overwhelm opponents mostly without having to outscore them in a shootout.

Three years removed from the franchise's first Lombardi Trophy, experts viewed the 49ers as an overwhelming favorite entering the 1984 season to win it all—a feat they would ultimately accomplish. As the season wore on, Dan Marino's record-breaking campaign created a split decision among the masses as to who would ultimately win the big game in Stanford. Like so many other teams, Montana and company systematically dismantled the Miami Dolphins in January.

Those positive vibes were put on hiatus that mid-October. A former, proud champion came to California to face the new-age face of NFL greatness. With a .500 record and starting backup quarterback Mark Malone, the Steelers were huge underdogs against the sublime pride of the NFL public.

Despite the tall odds, Noll realistically understood there was a way to beat the 49ers, though it wouldn't be easy—keep Montana off the field. Period.

Like the 2011 Steelers, who played Tom Brady and the Patriots on Halloween, the approach would have to be scoring points and dominating time of possession. For Ben Roethlisberger and crew, this meant attacking New England through the air—a successful feat that allowed the Steelers to improve their all-time record against California's golden quarterback to 2-6.

In 1984, that golden California gunner was Montana, and keeping him off the field meant a different approach in a vein very familiar to Steelers fans—running the ball. After all...

With odds already stacked against, what would the chances of an upset be in a Malone vs. Montana setup?

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Slim and none.

With this grand design in place by the coach who had won more Super Bowls than any other (a record that still stands), Noll was certainly pleased with the Steelers' opening possession. The 6-0 49ers defense saw the Pittsburgh running game seemingly gain four and five yards at every clip, controlling the sticks and establishing themselves on a fine first drive. Ultimately, Rich Erenberg (yep, that guy...) capped off the drive with a three yard touchdown plunge.

Pittsburgh would get the ball back quickly, engineering another long march down the field. Their second possession ultimately stalled near the San Francisco 30-yard line, but Gary Anderson's attempt from 48 yards was true. The field goal made the score 10-0 midway through the second quarter.

At last, Joe Montana's offense put together a march of their own. Not to be shut out in the first half, Joe "Cool" scampered for a seven-yard score moments before intermission, making the halftime score of 10-7 closer than the dominant Steelers' effort.

While Pittsburgh's offense got first downs in the third quarter, drives stalled shortly after the sticks moved. Yet, in a fine showing, the Steelers defense—coordinated by Tony Dungy and led by sack-master Mark Merriweather (15 sacks in '84) and interception machine Donnie Shell (seven)—returned the favor to San Francisco, not allowing the typically rhythmic offense to get its normal poetry into motion.

Toward the end of the third quarter, the defense was unable to get pressure on Montana, and the undefeated 49ers started to have their way. After an early afternoon of rest of execution, the approaching evening invited fatigue and execution (of a different kind) with it. San Francisco tied the game to start the fourth quarter.

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Then, after the Steelers offense stalled, which had become a disconcerting habit after halftime, Joe Montana and his deadly attack took to the field again. This time, the Steelers' hopes for an upset took a huge hit. Montana hit Wendell Tyler for the go-ahead score, and the 49ers had overcome a slow start to lead 17-10.

Order had been reestablished at Candlestick Park, and the world suddenly made sense again to NFL fans. Few were the Steelers fans, despite their deepest hopes for victory, that didn't have self-doubt trickle into their minds. Despite a perfect start that saw everything fall into place for Pittsburgh, San Francisco had turned momentum completely around.

Then, it happened. The offense had a gut check.

Showing fortitude, the Steelers responded with a 15-play, 83-yard drive. As time wound down in the final quarter, fans in the Steel City surely hoped that the unit could force overtime. First down after first down, the offense drove methodically down the field on the efforts of running backs putting in yeoman's work.

Leading the way in the contest was Frank Pollard with 24 carried for 105 yards. Most of those were tough-earned, physical, five-yard bursts.

After matriculating into the red zone, Pittsburgh had a 1st-and-goal, six yards out. Surprisingly, they went to the air, and Mark Malone's pass found iconic receiver John Stallworth to tie the game. While jubilation in Steelers Country resulted, their celebration was tempered by an ominous factor:

Three minutes remained for "Montana the Maestro's" magic.

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Instead of magic, hopeful 49ers fans and skeptical Steelers fans got tricked. Right outside linebacker Bryan Hinkle intercepted Montana, returning the football 43 yards deep into Steelers territory.

While they couldn't put the game away from near the end zone, the Steelers offense watched as Anderson kicked the ball through the upright from 21 yards away. Pittsburgh led 20-17, but time remained once again, forcing fans to consider Montana for a second time.

This time, the legendary quarterback answered the call.

With 1:42 remaining, Montana hit Dwight Clark to the San Francisco 38-yard line, hurried to the line before hitting Earl Cooper, found Cooper again to midfield, and the rhythmic nature of the two-minute drive was frightening to start.

After consecutive completions to Earl Cooper, Montana hit his fourth pass and nailed his intended receiver between the numbers- who couldn't hang on for the catch inbounds.

Any reprieve felt by Steelers Country was short-lived as Joe hit Craig for a first down before getting two more completions to Cooper, setting up San Francisco at the Steelers 20-yard line. With seconds left, Ray Wersching came in to attempt a 37-yard field goal. A successful field goal would send the game into overtime, giving the 49ers a shot to improve their record to 7-0.

Only now do we realize that his miss quite possibly prevented the second-ever undefeated NFL season. As his attempt sailed wide, 49ers fans fell into silence, while the elated Steelers jumped for joy!

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Their huge upset propelled Pittsburgh to 4-3. On one of the most underrated games in the history of a great franchise, the team recently removed from greatness beat the best team in the NFL.

The annals of time haven't recalled the '80s Steelers with fondness, despite their penchant for reaching the postseason and suffering losing seasons a deceptively low three times. Meanwhile, history remembers the 49ers as a legendary squad, rife with talent that knew how to win like men.

These reflections are, at least to a degree, accurate. Still, history doesn't recall any 49ers teams as undefeated.

Additionally, on one random Sunday in 1984, those who look back will recall the one day that reputations and prognostications were simply irrelevant.

It was the day when Montana fell to the Men of Steel and a day when Chuck Noll showed Bill Walsh that there was still a place in the NFL for an old dog—even without too many new tricks!