Who are the best quarterbacks in the NFL? That question has come up for decades, going back to the debates between the talent of Dan Marino and the success of Joe Montana.
How would you go about proving the worth of a signal-caller in 2016? Would you look at stats such as passer rating, his record in the playoffs or the number of awards, Pro Bowls and All-Pros he has on his resume?
In Bleacher Report's 28 Over 28 series, we'll break down and rank players who are at least 28 years old, which covers the majority of non-rookie-contract players league-wide.