# Analyzing the one-on-one drills

August, 9, 2013
8/09/13
11:00
AM ET
GREEN BAY, Wis. -- Throughout training camp, you may have seen references to win-loss records for players in the one-on-one pass blocking/pass rushing drill the Green Bay Packers employ almost daily.

While it’s not the only measure of an offensive lineman’s ability to protect the quarterback or a defender’s skill as a pass-rusher, it’s an important tool used in the evaluation process.
For example, the six offensive lineman who have worked primarily with the starters during the first two weeks of training camp (including the now-injured Bryan Bulaga) have a combined record of 60-10 for a winning percentage of .857. The rest of the offensive linemen have a combined record of 128-52 (a .711 winning percentage).

However, the problem with straight-up records is that they do not take into account who each player has been matched up against.

In order to better put those records into perspective, reader Luke Stanke -- a Green Bay native and graduate student at the University of Minnesota who has an interest in statistical analysis -- offered to devise a formula, similar to the Ratings Percentage Index (RPI) used in college basketball. The formula ranks the players involved in the drill based on my subjective results of each head-to-head matchup. Stanke has two metrics: a regular RPI and a weighted RPI.

He explained them this way: “The regular RPI is one-quarter winning percentage plus one-half opponent winning percentage and one-quarter opponents’ opponents winning percentage.” The weighted RPI, he said, is “a bit more complex, but the interpretation is the same as RPI.” He said the weighted RPI “does the best job of predicting the winner of a matchup.”

The rankings clearly aren’t perfect. While Bulaga, who tops the chart, was clearly the most dominant pass-blocker. No one would argue that outside linebacker Clay Matthews isn’t the Packers’ best pass0rusher. Yet Matthews hasn’t won a turn (albeit in limited reps) and ranks near the bottom of the list. You also will notice that the drill is slanted toward the offensive player, so a defensive player with a record close to .500 should be considered outstanding.

With that in mind, here are the rankings for every player who has taken a repetition in the one-on-one drills so far this preseason. We will update this a few times throughout training camp.