I introduced Graphing the Hitters earlier this month. The focus was on Productivity, defined as OBP and SLG.

In this week's edition of Graphing the Hitters, I'm going to concentrate on Plate Discipline. The graph below plots walk rate (BB/PA) on the x-axis and strikeout rate (SO/PA) on the y-axis for every qualified batter in 2009. The intersection of the MLB averages for BB% (8.88%) and SO% (17.96%) created quadrants that classify players as better-than-average in both (lower right), worse-than-average in both (upper left), or better-than-average in one and worse-than-average in the other (lower left and upper right).

Unlike Fangraphs, I believe the denominator for strikeout percentage should be plate appearances (rather than at-bats). For whatever reason, Fangraphs defines walk percentage as BB/PA but strikeout percentage as SO/AB. As a result, while the raw numbers were downloaded from Fangraphs, the BB% and SO% were calculated separately.

Note: You can download a spreadsheet containing the PA, BB, SO, BB%, and SO% of the 155 hitters here. This information can also be used to locate the 134 players not labeled in the graph below.

My first question following the Productivity graph was "Is Albert Pujols any good?" Well, after looking at the Plate Discipline graph, I've got to ask the same question once again. This time around, I'm going to shout out my question.

OK, I think I've made my point now. Not that it was really necessary. Everybody already knows that Pujols is better than good. I mean, this guy is great. In fact, he is on pace to become one of the greatest hitters of all time and perhaps the best or second-best righthanded hitter ever.

Pujols has played nine seasons in the major leagues. He has ranked in the top ten in batting average, slugging average, on-base plus slugging, total bases, and times on base every year. What is less known is that Albert has improved his walk rate every single season while reducing his strikeout rate by a third since his rookie campaign in 2001.

In 2009, Pujols had the sixth-highest BB% (16.43%) and the ninth-lowest SO% (9.14%). That is a remarkable combination. He was the only player in the top 50 in walk rate with a strikeout rate below 10.0%. You have to go all the way down to No. 57 in the walk rankings to find someone with a lower strikeout percentage (Dustin Pedroia). The Red Sox second baseman had the lowest SO% (6.30%) in the majors.

Pujols and Pedroia are two of only 13 qualified hitters with more walks than strikeouts.

Adrian Gonzalez led MLB in walk rate and walks (119) last year. He was one of five first basemen with more walks than strikeouts. Three second basemen, three catchers, one shortstop, and one third baseman also accomplished this feat, including three projected starters for the Boston Red Sox in 2010 (Marco Scutaro, Victor Martinez, and Pedroia). The St. Louis Cardinals are the only other team with more than one representative (Pujols and Yadier Molina).

At the other end of the spectrum, Yadier's older brother, Bengie Molina, had the lowest BB% (2.50%) in baseball. Bengie struck out in 13.08% of his plate appearances, which means he whiffed more than 5x as often as he walked.

Mark Reynolds had the highest SO% (33.69%). He set a single-season record with 223 strikeouts in 2009. The 26-year-old third baseman has played three seasons in the majors and owns the top two strikeout totals in the game's history. His SO and BB rates have increased each year. The good news is that his BB% has risen 29.2% while his SO% has advanced just 8.0% since his rookie campaign in 2007.

Russell Branyan (29.50%), Jack Cust (30.23%), Adam Dunn (26.50%), Ryan Howard (26.46%), Brandon Inge (26.69%), and Carlos Pena (28.60%) stand out for their high strikeout rates. However, Inge was the only one with a walk rate (8.48%) below the league average.

Lastly, there were 13 qualified hitters with walk rates over 15%. Other than Pujols, every player in this baker's dozen bats lefthanded or both. Therefore, I believe it is safe to say that the three-time MVP is truly unique. As the graphs have shown, Pujols is the most disciplined and productive hitter in the game today.