Will Harbaugh, Carroll be elite coaches?

San Francisco's Jim Harbaugh and Seattle's Pete Carroll will square off Sunday night. Getty Images

Similarities between the Seattle Seahawks and San Francisco 49ers frame an increasingly intense, combative rivalry heading into their Week 2 stare-down Sunday night. Both teams have young, multidimensional quarterbacks. Both teams emphasize a power running game with read-option flexibility. Both possess physical defenses built around size, strength and versatility. Plus, key members of the teams' front offices previously worked together, which is one reason for the shared vision.

Yet, for all these teams' similarities, their head coaches appear to be from different planets. The 49ers' Jim Harbaugh recites the gospel according to Bo Schembechler, relishes confrontation and years ago ranked among his cherished moments the time Garth Brooks wore his No. 4 Colts jersey at a concert. The Seahawks' Pete Carroll traces his coaching philosophy to John Wooden, promotes introspection through yoga and reportedly saw the Grateful Dead in concert two dozen times.

"Pete is energetic, fun -- positive, positive, positive," said Seahawks cornerback Richard Sherman, who played for Harbaugh at Stanford. "Jim is more stern -- it's going to be this way. He's old-school, like Bear Bryant and those guys that preached discipline."

Both Harbaugh and Carroll had success coaching in the Pacific-10 conference. Both have won NFC West titles and multiple playoff games since taking their current jobs. They are ascending and could one day earn universal recognition as elite NFL coaches. But how do they stack up now, and what do they need to do to reach elite status?

After speaking with several associates and NFL sources in the past week, here's a look at where Harbaugh and Carroll are perceived to be strongest -- and what might ultimately prevent them from joining the elite ranks.