How many QBs under Belichick?

This morning's "bubble watch" entry on Tim Tebow provides a springboard to look closer at how Bill Belichick has managed the quarterback position on the roster over his previous 13 years as head coach, in terms of numbers.

As Belichick said numerous times, he doesn't necessarily have a preference on how many quarterbacks the team keeps on its 53-man roster.

In 2000, Belichick felt there was enough value in a No. 4 quarterback, then-rookie Tom Brady, that it wasn't a hard decision to carry the high total of four. Other years, such as 2012, Belichick was comfortable with just two (Brady, Ryan Mallett). In 2006, the Patriots went half the season with two before bringing in veteran Vinny Testaverde as a third option in November.

So history doesn't provide us with many definitive answers, but it is a place to start when considering how things might shake out with Tom Brady, Ryan Mallett and Tebow this year.

2012: 2 (Brady/Mallett)

2011: 3 (Brady/Hoyer/Mallett)

2010: 2 (Brady/Hoyer)

2009: 2 (Brady/Hoyer)

2008: 3 (Brady/Cassel/O'Connell)

2007: 3 (Brady/Cassel/Gutierrez)

2006: 2/3 (Brady/Cassel -- Testaverde/mid-year)

2005: 3 (Brady/Cassel/Flutie)

2004: 3 (Brady/Davey/Miller)

2003: 3 (Brady/Davey/Huard)

2002: 3 (Brady/Davey/Huard)

2001: 3 (Bledsoe/Brady/Huard)

2000: 4 (Bledsoe/Friesz/Bishop/Brady)

Here are some of the considerations from a team perspective on the number of quarterbacks:

46-man roster rule on game-day. The NFL changed its "third-quarterback" rule prior to the 2011 season. Prior to that, teams could dress a third quarterback on game-day and that player wouldn't count against the then-45-man roster limit. The change in 2011 was to allow teams a 46-man roster on game-day and eliminate the third quarterback rule (the third QB couldn't enter prior to the fourth quarter, and if he did, it eliminated the first two QBs from playing). So on game-day teams now have to decide: Do we place a higher value on a 46th player who might be a core special teams contibutor (possibly 10-20 snaps per game) or the insurance of a third quarterback who likely won't play? The answer to that question can have a trickle-down effect when planning on the overall 53-man roster.

Economics. Part of the reason the Patriots might have released Brian Hoyer at the end of 2012 training camp was that he was due a $1.9 million base salary. It can be easier to absorb multiple backup quarterbacks if the salary numbers are lower. For example, this year, Ryan Mallett ($642,984) and Tim Tebow ($630,000), in combined salary, won't match Hoyer's salary from 2012. That could make it easier to keep both.

Planning for the future. Backup quarterbacks are sometimes in the mix with future years in mind. For the Patriots, they have Tom Brady signed through 2017, and then Mallett and Tebow through 2014. If Mallett has a productive preseason, he could become a potential valuable chip in a 2013 trade. If that turns out to be the case, having a No. 3 quarterback already in the system could be viewed as beneficial.

Practice squad. The opinion of some is that the best set-up is to have two quarterbacks on the overall 53-man roster, and then a third option on the practice squad. That gives teams the best of both worlds -- three layers of depth at the game's most important position, but only accounting for two roster spots. Specific to the Patriots, Mallett and Tebow do not have any practice-squad eligibility.