Baseball is a game that's defined by its records, in a way that's probably unlike any other. Even among casual fans, I would be that most know the significance of 714, and I'd bet that as many are aware of 4,256 and 511 [if you're not, just go and type the former into Wikipedia]. These evolve over the course of history; some marks previously considered unattainable are no longer out of reach, while others may never be seen again. For amusement, I thought I'd take a look at the single-season marks that are probably least likely to be surpassed.
I'm excluding 19th-century baseball stats, since those were from a very different game indeed [though respect is due to the likes of Matt Kilroy, who holds the all-time single-season strikeout record, with 513]. To come up with an objective number, I've ordered these by the percentage, by which the current record holder is in excess of the best number posted over the last decade.
10. Strikeouts, 14.7% : Nolan Ryan, 383 (1973) vs. Randy Johnson, 334 (2002)
I'm quite surprised how low this one ranked on the list, but the decade just manages to cover the tail end of the dominant force which was Randy Johnson. If you take out him and Curt, the next pitched on the list is a long, long way back - Justin Verlander's 269 strikeouts in 2009. We may have seen the end of the 300-strikeout pitcher, with the reduction in innings pitched more than countering the general increase in whiff-rate.
9. WHIP, 18.0%: Pedro Martinez, 0.7373 (2000) vs. Randy Johnson, 0.8996 (2004)
It's hard to over-state just how incredible Martinez was in 2000. In 217 innings, he allowed 128 hits and walked 32. That's an on-base percentage - not batting average - against of .213. Oh, and he struck out 288 batters, for a K:BB ratio of 8.9. It's hard to see anyone coming anywhere close to those kinds of numbers now. It would need to be a high-strikeout pitcher, to minimize balls in play, but would need great control. Verlander again, or perhaps someone like Matt Cain if he can cut back on the free passes.
8. Wild Pitches, 20%: Red Ames, 30 (1905) vs. A.J. Burnett, 25 (2011)
Burnett came as close last season as anyone has in a long time - the only other pitcher to reach that mark since the mid-60's was Juan Guzman, who uncorked 26 wild pitches in 1993. It takes an odd combination of wild effectiveness to challenge here, since if you're throwing the ball to the backstop that often, it suggests that walks and thus ERA will likely also be high. Burnett wasn't like that. While he had ten more WP than anyone else, his walks were only good enough for fifth-most in the majors.
7. RBI, 22.4%: Hack Wilson, 191 (1930) vs. Alex Rodriguez, 156 (2007)
The most derided of counting stats, depends on both a player's ability to drive in runs, and in those ahead of him to get on base. Wilson started all but one games at clean-up for the Cubs, most of them hitting behind Woody English and Kiki Cuyler, who sported on-base percentages of .430 and .428 respectively. And they tied for third in the league in triples, with 17 apiece, so Wilson could drive them in, even without a hit. But with a 1.177 OPS for the year, that typically wasn't the case. Hard to see such a triple-threat combination occurring again.
6. Runs, 23.8%: Babe Ruth, 177 (1921) vs. Alex Rodriguez, 143 (2007)
There seems to be a glass ceiling currently in operation, of around 140 runs in a year. 22 players over the past decade have managed between 124 and 139, with A-Rod the only one to push past that. Again, it's something where you are largely at the mercy of your team-mates hitting behind you. To score a lot of runs, the ideal combo would be a home-run hitter, with speed who can convert singles into being in scoring position. Which sounds like Matt Kemp, until I mention the third part of the equation, having colleagues who can drive you in, which certainly is not the 2012 Dodgers. Thus far, Kemp has driven himself in, more often than the rest of his team put together...
5. Home Runs, 25.9%: Barry Bonds 73* (2001) vs. Ryan Howard, 58 (2006)
Though in terms of numbers, this isn't the biggest gap, there is a great deal to suggest it may be among the most untouchable of marks. You'll note the * beside the number next to Bonds' name, and there is plenty of reason to believe this number was reached with the aid of illegal help. While it'd be an optimist to suggest these days are behind baseball entirely, there is more scrutiny and risk than at any time in the game's history. With the rewards being so much more these days as well, it'd take a real idiot to jeopardize their nine-figure contract for a shot at a tainted record.
4. Hit By Pitch (Pitchers), 52.4%: Chick Fraser, 32 (1901) vs. Kerry Wood, 21 (2003)
This ties into the wild-pitch thing somewhat, but there has definitely been something of a renaissance in this lately. HBP rate reached its nadir in the mid-eighties at a rate of just 0.13 per game in 1984, but more than tripled over the couple of decades which followed, reaching 0.40 in 2006. It's declined a bit since, but the 0.31 rate last season was not far off the 0.39 number from the year in which Chick Fraser set the record. Unsurprisingly, Burnett was the most recent to make a run, hitting 19 batters in 2010.
3. Triples, 56.5%: Chief Wilson, 36 (1912) vs. Curtis Granderson, 23 (2007)
Granderson came closer than anyone has managed in more than eight decades, could have increased his tally by more than 50% and still fallen short of the record. Wilson hit a triple in five consecutive games and two-thirds of his that year came at spacious Forbes Field, very conducive to triples, at 442 ft to center - the Pirates in 1912 would still have led the league in three-baggers, even if Wilson had none at all. Outfielders also tended to play shallower in those days. But to put his total into context, last season only six entire teams in the National League hit 36 triples. Unsurprisingly, the outfields of Petco and Coors helped the Padres and Coors to the lead, with 42 and 40.
2. Stolen Bases, 66.7%: Rickey Henderson, 130 (1982) vs. Jose Reyes, 78 (2007)
In 1982, Henderson was on first- or second-base with the next bag open 225 times. He had 167 stolen-base attempts [plus five of home]. So, more than three-quarters of the time, he'd try to steal when given a chance. Michael Bourn led the league in chances last season with 319, and that's the kind of player it would take - someone who gets on base a lot (as we saw in the Atlanta series), along with a high-success rate, like Bourn's 81%. But he tried less than one-quarter of chances, so would need to be a lot more aggressive. Maybe, if scoring continues to decline, the stolen-base might become vital to a team's success again. Until then, Rickey remains king.
1. Wins, 70.8%: Jack Chesbro, 41 (1904) vs. Randy Johnson, 24 (2002)
I could, to be honest, fill this entire list with pitching stamina categories. Starts, innings pitched, complete games, etc. The numbers for these are just insane. Chesbro, for example, started 51 games for the Yankees in 1904, completed 48 of them and threw 454.2 innings. It's very, very rare for a team now to have that number of innings thrown by any two pitchers in a season. Maybe we can take innings pitched into consideration. If we do, 20 qualifying pitchers since the 19th century have won better than one game per 10 innings of work. Only three were in the NL, Matt Morris, John Smoltz and Don Newcombe.