Most panelists ranked accuracy first on the list of traits they most value in a quarterback. Intelligence, work ethic, velocity, toughness, leadership, mechanics and a quick release also were important. Mobility was a plus, not a necessity. But playing the position well also requires a moxie not easily measured or explained.
"I've always had an expression I've carried with me a long way," said Meyer, who coached Namath and Ken Stabler at Alabama before coaching in the NFL for 22 seasons. "Talk about a good quarterback, and I say, 'Well, he can play cards.' There are some guys [who] can play cards, some guys [who] cannot play cards. All the good quarterbacks I've ever been around, they could play cards."
Harris, the Jacksonville Jaguars' vice president of player personnel and an NFL quarterback from 1969 to 1981, ranked toughness high on his list.
"Obviously, you need to have the physical tools," Harris said. "Once you identify those, toughness, making good decisions, work ethic and one's ability to make plays with the game on the line stand out right off the top."
Panelists agreed to submit rankings as long as their choices would remain private. ESPN.com adjusted for bias, taking note when a panelist assigned high rankings to former associates. Levy naturally favored Jim Kelly from their days together in Buffalo.
Meyer, who rates quarterback prospects for the Kansas City Chiefs while in semiretirement, remains partial to Namath and Stabler. Bratkowski backed up Starr with the Green Bay Packers, and he still has Starr's back.
Rooney, whose family owns the Steelers, has a strong affinity for Bradshaw.
A former longtime personnel evaluator, Rooney rated his 10 greatest quarterbacks across 14 categories, sending his hand-written breakdowns by mail. Levy, Rooney, Bratkowski and Kennan provided lists of their top 10 all-time quarterbacks, in preferred order. Haley singled out 10 without as much regard for order, but he spoke at length about all 10 and numerous others, providing insights that proved helpful. Harris, reached between Senior Bowl practices in Mobile, Ala., provided his top six. He also evaluated 50 quarterbacks across several key categories.
Meyer, Bratkowski, Kennan, Levy and Haley spoke at length about quarterbacks and what makes them great. Meyer declined to provide a top 10 list, but all panelists placed Brady among the greats, assuming he remains productive.
ESPN.com weighed their contributions, balancing rankings with anecdotal evidence, in an effort to create the best possible rankings. We sift through their contributions below.
Where Brady fits: Experts ranked him among the five most accurate passers; some thought he might be the most accurate in NFL history.
Quarterbacks can be many things, but if they're not accurate, they won't last long.
"I've seen so many strong-armed guys go through our league and never make a dent because they just were not accurate enough and it took them too long to throw it," Haley said.
Accuracy mattered long before Bill Walsh's short-passing offense took hold in San Francisco nearly 30 years ago, but the proliferation of similar offenses has heightened its value. Walsh's offense relied more heavily on receivers gaining yards after the catch. That meant quarterbacks needed to hit receivers in stride.