Chris Whalen’s Random Life

Well, quite a week one. I wanted to take the opportunity to take a look at the effect a QB, or more importantly a backup QB have on a game. AN average NFL quarterback completes about 50% of his passes, a top flight QB about 60%. So what does that really mean? Well depending on what offense a team plays and how many times that QB throws (I think the NFL average is 25 attempts per game) the difference is surpisingly small. Depending on whether your are the Steelers, throwing 20 times, or the Colts, throwing 35+ times, the difference between 50% and 60% is between 3-6 completions a game. That’s it. That and the TD to intertception ratio is what drives QB ratings. That really doesn’t tell the whole story. What you really want to know is what situations were the passes thrown in. What is the 3rd down success rate? What is the average gain on first down? And most improtantly, Yards per Attempt. A good view to where a QB is throwing the ball. Obviously a lower number means throwing more passes for less yardage. Short dump passes etc. Something in that 5-7 yard range speaks of a short passing ball control team. Anything north of 9 yards points to a vertical passing attack.

Tom Brady had a very high yards to attempt last year. Look this weekend for Matt Cassell to have a much lower yards per attempt this Sunday as a more ball control passing attack. More reminicient of the Patriots in ‘06 instead of ‘07. Higher completion percentage, but much shorter passes.

 The guys over at Cold Hard Football Facts and Pro Football Reference (http://www.pro-football-reference.com/blog/?p=581) did a great job figuring out what the backup QB effect is. THe blog I listed is where they did the math. In a nutshell the average difference in a given start between the backup and the starter is a drop off of about 2.3 points. Probably a bit mroe in the case of the Patriots, but I still bet not more than 5-7. What does that translate to? According to these guys the backup would win one less game per year. Adjusting for the high power of the Patriots offense, combined with the easy schedule they have this year I would think translates into more like 2 wins per year less for Cassell. This will be very interesting to watch, honestly I had no idea the mathematical difference between the backup and the starter were so small. What do you guys think?