Circa 1987.

On Saturday evening, I heard something on TV that I thought was interesting, and spat it back out on Twitter. A lot of people also found it interesting–I mean, a lot, way more than I had any idea how to deal with–so much so that I feel like I should really write about it. Here it is:!/Bill_TPA/status/188776185252163584

And it’s true: there are, as of yesterday, 15,855 different players who have ever had at least one plate appearance in the big leagues, going back to 1876. If you count through his “vs. batter” logs on Baseball-Reference (you have to scroll down and count the gray lines, grouping them by 25), Moyer has faced 1,417 different batters. 1417/15855 = 0.08937, or very nearly 9% of all hitters who have ever appeared in the major leagues. That’s a staggering amount of baseball history for one player to have had a hand in. It’s terribly impressive, as is Moyer.


Jamie Moyer has faced a wider cross-section of hitters than almost any other pitcher in history, which is really impressive, but is also the product of advantageous timing and a perfect storm of other luck-based factors. Kind of like how Tim Keefe racked up 342 career wins.

Tim Keefe was, apparently, a very good pitcher. Active for only fourteen seasons, from 1880-1893, he led his leagues in ERA and ERA+ three times each, starts, complete games, innings, and strikeouts twice each, and shutouts once. For his career, his 82.5 rWAR is 18th all-time among pitchers. But none of that, of course, is why the Veterans’ Committee put Keefe in the Hall of Fame in 1964; that was the wins, and only the wins. Keefe piled up 342 of those in his fourteen seasons, against 225 losses.

Which doesn’t tell you nearly as much about Keefe as it does about the time in which he played. In 1883 in the American Association, Keefe got 68 starts, completing all 68 (he was one of only two pitchers on his team, the good one), threw 619 innings, and was credited with 41 wins…but he didn’t even lead the league in that category (Will White had 43). His innings total that year alone would have put him in the top 20 innings leaders for 2009-11 combined. Keefe was a good pitcher, but so was Sal Maglie (who put up the same 127 ERA+ over 14 years, but managed just 119 wins). The eye-popping win total was a combination of Keefe’s talent, pitching for good teams, and, much more than anything else, the era in which he played.

I’ve come to realize that that 8.9% figure on Moyer is a lot like that. Everyone knows that Moyer has pitched forever. But while his pitching at all at age 49 is historically significant, his longevity on the whole is not; he had topped 200 innings only twice before age 35, and missed all of his age 29 and most of his age 28 seasons. Even if you skip the crazy Keefe-and-Old-Hoss years and start with the American League in 1901, Moyer’s longevity is near the top, but not at the top: 14th all time in games started (629), 28th in innings (4025.1), 14th in seasons with at least twenty starts (18), 3rd in seasons with at least one start (25; Nolan Ryan had 26, Tommy John had 27).

As relatively impressive as that is, I’m fairly confident that he’s roughly fourth and soon to move into second all-time in the number at issue here, total number of different batters faced. Here’s how I think I know. This is the list of pitchers with the most batters faced since 1948 (the earliest year Baseball-Reference has the “vs. batter” numbers). Moyer’s 17th in total batters faced, but has faced significantly more different batters than all but two of the guys in front of him. Phil Niekro faced the most batters over that period, 22,677 of them from 1964 through 1987, nearly a third more than Moyer’s 17,123…but Niekro faced only 1,185 different batters, 232 fewer than Moyer. Robin Roberts faced more than 2,000 more batters than Moyer did, but nearly 600 fewer different ones (just 886).

That gives you the single biggest factor; pitchers who have pitched later in time have gotten to face a greater variety of batters. That’s kind of obvious, right? For much of Roberts’ career, there were 16 teams in all of baseball, then 18, then 20, so he was necessarily facing the same teams (and thus players) more often than pitchers in a 30-team league would. Not only that, but from 1994 on, you’ve got interleague play, which exposes modern pitchers to several rosters full of players they might not have had any chance to face in prior eras. The likes of Roberts and Spahn are so far behind that I’m comfortable just writing off everyone from pre-1948 along with them. Walter Johnson and Cy Young threw a ton of innings, but they were throwing to the same guys over and over.

But then you’ve got Roger Clemens, who pitched to 3,100 more batters than Moyer did (20,240) and started 79 more games, and in substantially the same era, yet only 1,248 different ones,  169 fewer than Moyer. That gets to two of Moyer’s other advantages in this race: he (1) has pitched for many different teams in many different divisions (every division save the AL Central, now), and (2) has had about a third of his career games and innings in the NL. Clemens, meanwhile, pitched about 90% of his career in the AL East, and (thus, duh) in the AL, meaning he not only faced a lot of the same players, but didn’t get to face pitchers (much more likely to be a different one every time you face a team than the DH), or the pinch hitters for them.

So, as impressive as Jamie Moyer is — and I’m impressed by almost literally everything about Moyer — it’s important to note the special set of circumstances beyond his relentlessness that has allowed him to face close enough to 10% of everyone ever to step into a big-league batter’s box. He’s switched teams frequently, he’s spent a lot of his career in the NL, and, most importantly, he’s pitched during a time where, for much of his career, he’s had 13-15 intra-league opponents and five or six interleague opponents every year. He’s had an incredible, very long career, but he’s had to be in the right place at exactly the right time to get to that 8.9%. Just like Keefe was really good but not 342-wins-good, Moyer’s been incredibly long-lived, but just not quite 8.9%-long.

I’ll close by telling you who the other leaders are, because if you’ve bothered reading this long, you’re probably wondering:

Nolan Ryan pitched to 1,417 different hitters in his career, exactly the same number Moyer’s currently on (with 5,452 more batters faced), so odds are Moyer passes him with his next start (he’s never faced Paul Goldschmidt, for instance). Ryan didn’t get to pitch in interleague play or after the last couple expansions, of course, but he does have an incredibly long career on many different teams and divisions.

Tom Glavine pitched to 1,427 different hitters (with nearly 1,500 more batters faced), so Moyer may well catch and pass him this year. He pitched in the right era and in the right league, but spent his entire career in the NL East (and in only 22 different years, as opposed to Moyer’s 25).

Your all-time leader, though, now and for the foreseeable future, is Greg Maddux, who pitched to a whopping 1,535 different hitters, 118 more than Moyer (with 3,298 more batters faced). Maddux pitched at the right time, spent his whole career in the NL, and switched teams and divisions a lot. It’s going to be a great honor for guys to be able to tell their children and grandchildren that they once faced Greg Maddux…but then, very nearly one in every ten big leaguers of all time have done it (9.7%, to be exact), so how special are you, really, grandpa?