It's not the best rivalry in the NFL. It's not the flashiest. It might not even be familiar to fans under 25, but the San Francisco 49ers and the New York Giants evoke powerful memories for football fans dating back three decades. And now that both clubs have returned to the top of the NFC, it's a duel that's quickly gaining prestige.

The rivalry began, like so many others, as the teams experienced some of the best years in respective franchise history. The 49ers, who hadn't made a playoff appearance in almost a decade and had gone 8-24 over the previous two seasons, came out of nowhere in 1981 to win the Super Bowl. That year a young quarterback named Joe Montana led San Francisco to a 13-3 season, the best record in the league.

In the divisional round of the 1981 playoffs, the 49ers faced another team which was in unfamiliar territory. The New York Giants were making their first playoff appearance in two decades. After a narrow victory over the Philadelphia Eagles, the Giants were overpowered by a San Francisco squad that had gone 12-1 over the season's final 13 weeks.

The teams met three more times in the playoffs in the next five years, and twice the victor of that game went on to win the Super Bowl.

Perhaps the most memorable showdown between the squads took place in the NFC Championship in January 1991, an extremely physical contest which saw both starting quarterbacks leave the field with injuries in the fourth quarter. Jeff Hostetler of the Giantsmanaged to return after a hit to the knees from defensive tackle Jim Burt in the fourth quarter, but Montana was taken out of the game after a vicious tackle by Leonard Marshall produced a concussion and a broken finger. The Giants won, 15-13, on a game-winning field goal by Matt Bahr.

After meeting in the playoffs five times in a nine-year span between 1982 and 1991, the two teams played just twice in the next two decades. In 1994, the 49ers produced one of the largest routs in playoff history, a 44-3 trouncing of the Giants. In 2003, New York blew a 24-point lead and the game ended on a wild field goal attempt gone wrong and an officiating controversy.

The NFC Championship game in January 2012 brought the teams together with the Super Bowl on the line for the first time in 21 years. And fittingly, the game went into overtime, where New York kicker Lawrence Tynes booted the Giants into the Super Bowl.

San Francisco and New York squared off on Sunday, with the Giants proving victorious over the 49ers for the second straight game. While the teams are the same, this version of the rivalry is completely new. Whereas coach Bill Walsh and the 49ers pioneered the West Coast offense in the 1980s, now San Francisco wins on the strength of its defense (the 49ers boast the NFC's stingiest unit). And while the Giants still have a menacing pass rush reminiscent of the days of Marshall and Lawrence Taylor, New York is winning because of Eli Manning and the NFC's highest-scoring offense.

True, this showdown lacks the geographical component of the rivalry between the Chicago Bears and the Green Bay Packers, or the historical significance of the Indianapolis Colts and the New England Patriots. And there is no bad blood between San Francisco and New York like there is between the Baltimore Ravens and the Pittsburgh Steelers. And for these reasons, it might never reach the upper echelon of NFL rivalries.

But these are two of the league's most storied franchises, and they appear to be paving the way for several more pressure-packed contests and perhaps even another Super Bowl berth. It doesn't get much better than that.

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