The other day I was looking at the all time leaders in hits per nine innings pitched on Baseball-Reference.com. I went there knowing that Nolan Ryan was first all time, but the list of names I saw in the top ten was very interesting. It's essentially a "Who's Who?" of the pitchers throughout history I'm most fascinated by. Some are famous. Some are not. I wanted to take a look at each today

Nolan Ryan: We all know Nolan Ryan. I'm not going to lie—Ryan is my favorite pitcher of all time. Many feel as though Ryan is overrated. I happen to think he's both overrated (look, he's not the greatest pitcher of all time) and underrated (he certainly wasn't "just a .500 pitcher") at the same time. Baseball-Reference's WAR ranks him 16th all time (among pitchers), nestled between Bob Gibson and Steve Carlton. That's not bad company. Sure, some of his value comes from longevity rather than sheer dominance. That's why we have wWAR, which ranks Ryan 22nd all time (but 16th if you exclude the inflated wWAR totals of 19th century pitchers). The only flaw on Ryan's record is his wildness. With the Mets and Angels, his BB/9 was 5.5. With the Astros and Rangers, it dropped to 3.8. Not only did Ryan post the best H/9 of all time, he did it by pitching an absurd number of innings. Many pitchers here were either relievers or flamed out quickly (therefore not having much of an end-of-career decline). Ryan pitched 27 years. And he owns a rate stat record by that much. Simply remarkable. Out of the top 50 single season H/9 ratios, Ryan owns ten. In fact, when he was 44 years old he turned in the third best H/9 ratio ever (5.3 H/9 in 1991). What will you be doing when you're 44?

Sandy Koufax: The man Ryan beat for this record was the pitcher he idolized. Like Ryan, Koufax's BB/9 numbers (and the rest of his statistics) had a sharp turning point. From 1955 to 1960, Koufax posted 5.3 BB/9. From 1961 to his abrupt retirement following the 1966 season, his BB/9 was 2.3. Koufax's K/9 trailed Ryan by 0.2 and his H/9 was a bit worse (0.2 difference). He walked a full batter and a half less than Ryan, but he did it in less than half the innings Ryan threw. Because of his short career, Koufax only posted 54.4 WAR (63rd all time). But he's one of the guys wWAR was built for, as he jumps all the way up to 97.7 (34th all time).

Sid Fernandez: Here's the first "wait, what?" entry on our list. Like most pitchers on this list, Fernandez was a strikeout machine. He had some control issues early in his career, but settled down. On three occasions he led the league in H/9. However, he was constantly slowed by injuries and totaled just 1867 innings. Many attributed his injuries to his weight.

J.R. Richard: I have always been incredibly fascinated by J.R. Richard. If you're not familiar with Richard, you need to learn about him. From 1976 to 1980, he went 84–55 for the Astros, accumulating a 2.79 ERA (with one ERA title), a 121 ERA+, 1163 strikeouts in 1239 innings (including two seasons over 300), and 534 walks (including league-leading totals of 151 and 141. He was absolutely unhittable, touching 100 mph with his fastball and yielding just 6.6 hits per nine innings during that stretch (and 6.9 for his career). During 1980 he was incredible, going 10–4 with a 1.90 ERA and 119 Ks in 17 starts. But after the Al Star break—and after repeatedly telling the Astros he wasn't feeling right—he collapsed due to a major stroke. He never pitched in the major leagues again.

Andy Messersmith: Along with Dave McNally, Messersmith broke down the reserve clause in 1975 as a result of the Seitz decision. After that, the era of free agency emerged. Messersmith actually turned in nearly all of his career value before the case (29.4 of 35.6 WAR). After signing with Atlanta as a free agent, he posted 5.0 WAR in 1976 and 2.3 WAR in 102 1977 innings. He was widely considered a failure because of his 16-15 cumulative record and shipped out of town before the contract was complete. Injuries forced him into retirement quickly and early, leading to a very short decline. As a result, his shiny 6.9 H/9 ratio stayed intact (along with decent K/9 and BB/9 marks of 6.6 and 3.4, respectively).

Mariano Rivera: The most remarkable thing about Mariano Rivera's appearance on this list is that he's not first. The fact that five pitchers—five starting pitchers with far more innings than Rivera, no less—appear ahead of him surprises me. Rivera is 13th all time in ERA, but not a single pitcher ahead of him is remotely "modern". He places third all time in WHIP, behind just Addie Joss and Ed Walsh. Joss, like Rivera, has no decline built into those numbers (since Joss tragically passed away in 1911). Rivera owns the best walk rate on this list, but also threw the second fewest innings (placing him ahead of the next pitcher on the list).

Trevor Hoffman: It often seems where there is a Rivera on a list like this, there is sure to be a Hoffman. The two feature similar hit rates and innings pitched, but Hoffman actually has a 1.2 K/9 advantage while Rivera has a 0.4 BB/9 advantage. Of course, in ERA+ (Rivera's 205 to Hoffman's 141) and WAR (54.9 to 30.8), there is absolutely no contest between the two.

Hoyt Wilhelm: Perhaps the most unique pitcher in baseball history, Wilhelm has the lowest K/9 on this list. Despite being primarily a relief pitcher, his innings total is actually higher than several of the starting pitchers. While many pitchers on the list are fireballing strikeout artists with iffy control, Wilhelm was a knuckleballer. How do his rates compare with the most valuable knuckleballer in history, Phil Niekro? Niekro surrendered 8.4 H/9 and 3.0 BB/9 while striking out 5.6 per nine. Wilhelm's numbers are 7.0, 3.1, and 6.6, respectively. Of course, Knucksie also threw 3150 more innings…

Sam McDowell: Like J.R. Richard, Sam McDowell is another pitcher I have always been fascinated by. I sure do love the wild, flamethrowing types. Richard and McDowell were both similar in the respect that they had a stretch of undeniable dominance. McDowell was simply remarkable in his stretch, which lasted from 1964 to 1971. In that stretch, he accumulated 41.6 WAR. His career total is 41.2, meaning the three seasons before and four seasons after that stretch were worth a total of -0.4 WAR. In addition to WAR totals of 4.6, 8.0, 4.5, 1.0 (injury marred year), 4.9, 6.3, 8.2, and 4.1, he posted K/9 numbers of 9.2 (led league), 10.7 (led league), 10.4 (led league), 9.0, 9.5 (led league), 8.8 (led league), 9.0 (led league), and 8.0. He twice surpassed 300 Ks, topping out at 325 Ks in 1965 (the same year he won the ERA crown with a 2.18 mark). Injuries (and later alcohol) ended his incredibly promising career. McDowell actually posted a career wWAR of 65.3, which places him less than four wins shy of the Hall of wWAR.

Kerry Wood: Yup, that Kerry Wood. Circa 2003, Wood was far and away my favorite pitcher in the league. You see, when Nolan Ryan retired from baseball in 1993, I kind of drifted from the game a bit. Part of it was the strike, part of it was high school years. Mark McGwire and Sammy Sosa brought a lot of people back. Kerry Wood helped bring me back that year. I looked at this flame-throwing Texan and thought, "Oh, so he's like Nolan Ryan." I was hooked. While Wood's big league career was sidetracked by injuries, I was able to experience "what could have been" by managing Wood on my beloved sim baseball team. For me, Wood retired with 253 victories and a new record 5716 strikeouts. Of course, "The Real Kerry Wood" didn't have the same results. But goddammit he had the same talent.

There you have it—the top ten. I love the list. There are a lot of great pitchers with great stories behind them.