A Washington, D.C. taxi driver rated former Denver Broncos' quarterback John Elway the #1 quarterback of all-time, and then was shocked to discover Elway was sitting in the backseat of the cab.

According to the Denver Post, Elway was in town for the presidential inauguration when he took a ride in the unsuspecting cab driver's taxi. It's not that Elway was trying to be sneaky, it's just that with other people in the car, the driver failed to notice the highly recognizable Hall of Famer.

The cab driver is a Pittsburgh Steelers fan and listed Tom Brady and Ben Rothlisberger at #2 and #3 on his all-time list of great NFL quarterbacks.

This could have turned out very differently. Just imagine the cab driver's embarrassment had his comments been less than complimentary of John Elway. There could have been major egg on the face, and big-time foot-in-mouth!

Fortunately, the taxi driver was a well-informed, unbiased football fan who recognized John Elway as the greatest of all time -- even though he didn't recognize him in his back seat.