To borrow from Jim Harbaugh, weâ€™ve â€œdefinitely noticedâ€ whatâ€™s been going on with his San Francisco 49ers and Pete Carrollâ€™s Seattle Seahawks this offseason.

It hasnâ€™t taken longâ€”since December, in factâ€”for San Francisco vs. Seattle to become the NFLâ€™s newest premier rivalry. It also will be a while before any other matchup in the league trumps it.

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In the previous 11 seasons that the Seahawks and Niners have been together in the NFC West, the familiarity to breed contempt has always been there. Missing until late 2012, however, was both teams playing a high level of football at the same time. Now they're built to be Super Bowl contenders for a long time.

The competitive fires between Harbaugh and Carroll were stoked before they got their current jobs. In the three seasons they were college coaching counterparts in the Pac-12, Harbaughâ€™s Stanford Cardinal went 2-1 against Carrollâ€™s USC Trojans. The meme of "smart-school upstart" (Harabaugh) upending "big-school bully" (Carroll) helped set up the contrast for their NFL battle of will and wits.

Carroll, with his rah-rah style and defensive acumen, took the Seahawks to a division title in his first season in 2010, albeit with a 7-9 record. Harbaugh joined the Niners a year later, and with his unwavering intensity and offensive foresight, put them on top.

Not much separated the teams last season. San Francisco did two things a little bit better to get to the Super Bowlâ€”finish a half-game higher in the standings and complete an improbable playoff comeback in Atlanta.

After their sizzling late-season surges, both teams are well aware that they're close to winning it all this season. The coaches, the players under them and the decision-makers above them, have all acted like it.

Harbaugh got in a jab early this month, pointing out that several Seahawks players have run into trouble with performance-enhancing drugs. â€œ Play by the rules â€ was his subtle directive to his team. In a not-so subtle response by one of those players who were suspended, Seahawks cornerback Brandon Browner said he wanted to â€œput his hands around Harbaughâ€™s neck .â€

As you would expect, Carroll, came back with nothing but praise for Harbaugh. â€œTheyâ€™ve done a marvelous job since Jim took over and theyâ€™ve done it all on the field,â€ Carroll said.

In an interesting twist, Carrollâ€™s Trojans were the Goliath, but in the NFL, itâ€™s Harbaughâ€™s 49ers with the big, bad reputation and the championship pedigree. The Seahawks are still chasing their first ring (their only Super Bowl appearance was in SB XL), and still trying to get the noisy Seattle faithful their first pro championship since 1979. The city of San Francisco, in addition to having five Lombardi Trophies and the reigning NFC champs, boasts the World Series champs from two of the past three years.

Last year, Seahawks cornerback Richard Sherman â€”who played for Harbaugh at Stanfordâ€”identified the Ninersâ€™ coach as the â€œbullyâ€ in the present scenario. The outspoken Sherman is a perfect mouthpiece for Seattle in the rivalry: He strikes the right balance of playing the "disrespected" card while also having the swagger to reap on-field rewards.

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Niners general manager Trent Baalke and Seahawks counterpart John Schneider have worked to keep up with each other as well. Both are dealing from positions of strength, because neither one has had to fix much this offseason.

Itâ€™s not a coincidence that 49ers traded for a dynamic, versatile receiver, Anquan Boldin, in the same March week the Seahawks acquired Percy Harvin. Or that both teams reloaded their strong front sevens with more pass rushers. Or that the 49ers answered the Seahawksâ€™ aggressiveness on the free-agent market by loading up on draft picks.

As much as football is a team sport, an elite tete-a-tete still centers on marquee individual matchups. When we think about the heyday of New England Patriots vs. Indianapolis Colts, we think Tom Brady vs. Peyton Manning. Their personal duel for all-time supremacy has carried over to the Patriots-Denver Broncos series.

Harbaugh vs. Carroll has been compelling for years, but the current quarterbacksâ€”the Ninersâ€™ Colin Kaepernick and the Seahawksâ€™ Russell Wilsonâ€”make the rivalry's future so much more exciting.

Andrew Luck, Robert Griffin III and Cam Newton may have their time soon, but Kaepernick and Wilson already have playoff victories. While weâ€™re wondering if those others can be as efficient and durable, the 49ers and Seahawks are blessed with guys who can run but whose best asset is their strong, accurate arms.

Itâ€™s hard to believe that Kaepernick and Wilson have dueled only once, a 42-13 Seahawks rout in Seattle last Dec. 23 in which Wilson was the much better quarterback. As both enter their second years as full-time starters, they already have the makeup of cool veteran leaders such as Brady and Manning, and they have the potential to match the latter two's passing accomplishments.

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Just as much as Brady is an extension of Bill Belichick, and Manning was of Tony Dungy, Kaepernick and Wilson also embody their coaches' philosophies.

From the time he became the full-time starter over Alex Smith in the middle of last season, Kaepernick has followed Harbaughâ€™s steely resolve that things be done the right way. Wilson, who was handpicked after a truly open competition in the preseason, carries Carrollâ€™s enthusiasm and positive youthful energy.

With leading men like that, 49ers-Seahawks is just getting warmed up as a riot of an act.

Rams tough, too

Just in case we forgot which NFC West team went undefeated in division play last season, St. Louis Rams defensive end Chris Long provided a reminder last week. Prompted by cornerback Cortland Finnegan calling former Rams and current 49ers safety Craig Dahl â€œlame and weak,â€ Long tweeted on June 12 that it had been â€œ528 daysâ€ since his team last lost to San Francisco.

St. Louis got a win and a tie against the Niners last season, split with Seattle and swept Arizona to go 4-1-1. The Rams announced that in just one year with Jeff Fisher, they were ready to step into the ring with the 49ers and Seahawks.

The Rams, who have their own tough defense led by Long and Finnegan, canâ€™t be ruled out as playing spoiler in the NFL's toughest division, but in for that to happen St. Louis must win outside the division (it was 2-8 last year) and get quarterback Sam Bradford to raise his play with an improved supporting cast of skill players.

The 49ers and Seahawks are on the short list of favorites to win the NFC because of Kaepernick and Wilson. A true breakout season from Bradford will give the West a good chance of having three playoff teams.