Then again, he could be the second coming of Scott Mitchell.
This is the difficult talent assessment that must be made by general managers whose franchises are seeking new starters in 2009.
At a position where elite talent is rarely available in free agency, Cassel is the most intriguing quarterback set to hit the market. Since Brady suffered a season-ending knee injury in Week One, Cassel has shown marked improvement while directing New England to a 7-4 record.
Cassel became only the fifth quarterback in NFL history to post consecutive 400-yard passing games during last Sunday's 48-28 victory at Miami. He has size (6-foot-4, 230 pounds), athleticism (84 rushing yards in the past two games) and a strong arm.
"He's really proving himself being his own guy," Miami nose tackle Jason Ferguson told Dolphins media before the game. "He's not the replacement of Brady. He's got his own name."
If he continues to shine the rest of this season, Cassel could very well command a Brady-like contract with at least $20 million in guaranteed money. But before paying him like the NFL's top-tier quarterbacks, interested teams must be convinced that Cassel can thrive outside of New England.
Mitchell is proof that such an assessment isn't easy.
Fifteen years before Cassel picked apart the Dolphins defense, Mitchell was enjoying similar success playing inside the same stadium. When Dolphins legend Dan Marino ruptured his Achilles' tendon in Week Five of the 1993 season, Miami turned to a replacement who had attempted just eight passes in his first three NFL campaigns.
Mitchell played surprisingly well—well enough to prompt some fans and media to speculate that he may be a better long-term option than Marino. The Dolphins weren't fooled. Detroit was, signing Mitchell during the 1994 off-season to what was then considered a major free-agent contract (three years, $11 million).
Mitchell had his moments during five Lions seasons-including a 4,338-yard, 32-touchdown effort in 1995-but he never led the team to a playoff victory even with Hall of Fame rusher Barry Sanders in the same backfield.
Just as damning, Mitchell didn't possess many of the other qualities expected from the position outside Xs and Os.
"He was never the quintessential leader," a former member of Detroit's front office said. "He didn't have a presence about him. He couldn't bond with the guys. The guys didn't believe in him."
Cassel's leadership skills will come under heavy scrutiny by potential suitors. He has the luxury of being a foot soldier on a veteran Patriots roster that has reached four Super Bowls with Brady. Cassel must be a general elsewhere, especially if he joins a lesser squad that hasn't come close to hitting those heights.
The expectations will be much higher than when Brady was initially replaced by Cassel, whose last start had come in high school. How will the 26-year-old Cassel respond to even more intense scrutiny? Can he thrive in a different kind of offense than what the Patriots run, especially if he doesn't have the services of exceptional wide receivers like Randy Moss and Wes Welker?
When he was Miami's general manager in 2004, Rick Spielman tried making those same projections about A.J. Feeley, who had shown promise in his five career starts for Philadelphia in 2002. Spielman did extensive film study comparing Feeley to six other quarterbacks who were potentially available via trade or free agency as well as the three incumbents on Miami's roster (Jay Fiedler, Brian Griese and Sage Rosenfels).
Trying to identify traits in emerging quarterbacks, Spielman dissected Marc Bulger, Matt Hasselbeck and Jake Delhomme both before and after all three ascended to starting roles. Spielman even did specific statistical analysis, like how the quarterbacks he was scouting fared when leading or trailing by a touchdown in the fourth quarter.
And he was still wrong.
Spielman traded a second-round pick to Philadelphia for Feeley and signed him to a five-year, $18 million contract. Both proved huge mistakes.
Feeley had starting-caliber physical skills but sorely lacked other intangibles. He didn't inspire confidence in his teammates. The comfort Feeley had in Philadelphia's West Coast-style scheme wasn't there, nor was the same quality of coaching or offensive talent surrounding him.
On and off the first-team offense, Feeley was 3-5 as a starter for a Dolphins squad that finished 4-12. The following year, Feeley was traded to San Diego. He has since returned to Philadelphia and is currently a third-stringer.
"The unknown part of the quarterback is the 'It' factor," said Spielman, who is now Minnesota's vice president of player personnel. "You take a chance because you see the numbers and the ability on film. That's objective, not subjective...But do they have that magnetism, that quality where they can lead a group of 10 other men when the offense is on the field? Unless you've been with those guys before, you don't really know that until they get there."
A general manager who has closely studied Cassel believes he won't be a one-year wonder. Warner and Brady proved otherwise as well.
"It's a gamble and a lot of money will be invested in Cassel," the general manager said. "But I truly believe that he has the full package."
The gift wrapping will be off soon enough.
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