Football Scientist: Giants vs. Jets, Part 4 - Offensive line & RBs in run game

This is Part 4 of a seven-part series looking at which team is better from a metric perspective, the Giants or the Jets? The Jets took a 1-0 lead and then extended it in Part 2. The Giants closed the gap to 2-1 in Part 3.

Before getting into the specifics of this analysis, it would be useful to take a moment to give an overview of The Football Scientist (TFS) run-grading system.

The centerpiece is the ROBIN block grading method. ROBIN stands for Results-Oriented BINary. The binary part of the equation means that each block is given a win or loss designation. The results-oriented segment indicates that the results of the block are all that matters -- it isn't designed to grade the specifics of run blocking technique. If the block works, the system counts it as a win.

So what is meant by a win? There is a lot that goes into that, but the simplest explanation is if the blocker moved his defender out of the way to create a seam for the runner to go upfield, he is given credit for a Point of Attack (POA) win. If the defender does anything to disrupt the run (e.g. stuffs the gap, gets past the blocker into the backfield, etc.), it is considered a POA loss for the offense. (Quick note on POA blocks -- there are occasionally blocking battles that occur away from the Point of Attack that are factored into the win/loss percentage ... e.g. terrific pursuit by a defensive end on the backside of a slant run, but by and large the system sticks to measuring POA blocks.)

In doing overviews of team blocking, there are two metrics that have stood out over the years as the best measuring tools.

The first is Good Blocking percentage. This metric came about after I did some studies on running backs to determine how well they did when they received good blocking (defined as when all POA blockers win their POA battles) and when they received poor blocking (defined as when one or more POA blockers loses his POA battle).

In the two seasons worth of studies I did on this, some benchmarks of success became clear. A good offensive line will post a Good Blocking percentage in the 75-80% range. An average O line will notch a 70-75% total and a subpar blocking group will post anything at or below the 70% mark.

So far in 2010, the Jets would be ranked as one of the good blocking O lines. According to the TFS count (which include blocking plays with penalties (they always count as a POA loss), but don't include scramble runs or kneeldowns), Gang Green has 217 POA runs. They have tallied 170 Good Blocking plays for a Good Blocking percentage of 78.3%.

The Giants haven't fared quite as well in this area. The TFS count has them at 198 POA runs, with 141 Good Blocking plays for a Good Blocking percentage of 71.2%.

Who Owns N.Y.?

There's talk of a Jets-Giants Super Bowl, but why wait to find out who's better? Over the next several days, KC Joyner will crunch the numbers.
Part 1: The receivers
Part 2: The secondary

Part 3: O-line/RBs in passing game
Part 4: O-line/RBs in running gameThat gives the Jets an early lead in this category, but it also leads to the second part of the aforementioned studies. After reviewing the league totals for RBs, it quickly became clear that no running back, not even Chris Johnson or Adrian Peterson, will gain many yards on plays with poor blocking. Most backs end up with a YPA of 1-2 yards in this category, with some going to the 2-3 mark and some ending up in the 0-1 range.

What that means is the true differentiation of a running back, and therefore a running attack, comes from how well a back performs when he is given good blocking.

The rules of thumb here are the elite runners will post a Good Blocking YPA (GBYPA) of 7-9 yards. Good backs will end up in the 6-7 range. Average backs end up between 5.5 and 6 yards and below average backs tally less than 5.5 YPA.

The Giants' runners as a whole are so far in the good back category, as they have gained 917 yards on those 141 Good Blocking runs for a 6.5 GBYPA.

The Jets runners don't fare quite as well, as they have gained 986 yards on 170 Good Blocking runs for a GBYPA of 5.8

It isn't just the overall count where the Giants have the lead. They also fare better with both their #1 and #2 runners:

#1 running back -- Ahmad Bradshaw vs. LaDainian Tomlinson

Bradshaw -- 97 Good Blocking runs, 668 yards, 6.9 GBYPA

Tomlinson -- 84 Good Blocking runs, 518 yards, 6.2 GBYPA

#2 running back -- Brandon Jacobs vs. Shonn Greene

Jacobs -- 40 Good Blocking runs, 230 yards, 5.8 GBYPA

Greene -- 63 Good Blocking runs, 328 yards, 5.2 GBYPA

Now we need to put these two sets of numbers together to determine which is more important -- Good Blocking percentage (where the Jets have a 7.1% lead) or Good Blocking YPA (where the Giants have a .7 of a yard lead).

Let's figure this out by using a 500-carry season as the benchmark (both teams might end up with more carries as a whole, but the 500 total is good because it is a round number and would factor out QB runs, kneeldowns, etc.).

Take 500 carries and multiply it by 7.1% and it means the Jets will have about 36 more Good Blocking runs over the course of a season. Multiply 36 by five yards (the rough difference between the gain on a Good Blocking and Poor Blocking play) and it equals a 180-yard advantage for Gang Green.

Now let's do the same thing with the .7 of a yard GBYPA advantage for the Giants. Multiply 500 by 71.2% (the Giants current Good Blocking percentage) and it equals 356 runs. Multiply 356 by .7 and it equals a 249-yard edge for the Giants.

249 may not be a lot larger than 180, but it is larger, so the Giants pull out a close win in this category.

Edge: A close victory for Big Blue. The series is now tied 2-2.