Although NFL fans know what those two star quarterbacks can do, uncertainty looms throughout the league today with several new faces under center.
Green Bay's Aaron Rodgers has officially been ruled out in Week 15, meaning Matt Flynn will get his first career NFL start against the Patriots.
Elsewhere, golden boy Tim Tebow will make his first career start today for the Broncos as they travel to Oakland to face the Raiders.
With Rex Grossman taking over as the Redskins' starting quarterback this week, Donovan McNabb's tumultuous days in Washington could already be over.
Here's a closer look at these stories and other happenings throughout the NFL in Week 15.