Yesterday I encountered a discussion regarding who had the best year in baseball in the 1970s. This made me start thinking about who had the best year of each decade. I want to mull over a few choices, but this was my initial reaction:
1890s: Hugh Duffy, 1894
Duffy led the league in home runs with 18--a lot back then--and batting average at....440. That'll work! Drove in 145 (in 125 games), had an on base percentage of .502.
1900s: Nap Lajoie, 1901; Ty Cobb, 1909
This one was tricky, because baseball at the start of the decade was much different than baseball at the end of the decade, when the ball was well and truly dead. Hence, two Triple Crown winners. Lajoie hit .426, with 14 homers and 125 RBI. Cobb had 9 home runs, 107 RBI, batted .377, led the league with 76 steals. It is worth mentioning that Cobb, who people erroneously think had no power, had eleven seasons in the top ten in home runs. There was no power at the time. But Cobb had as much as anyone, for a long stretch. We also could go with Christy Mathewson in 1908 with his 37-11 record against a 1.43 ERA. He pitched a mere 390 innings. The league leaders at the end of this season will be around half of that.
1910s: Walter Johnson, 1913
The best seasons, win/loss-wise, in pitching history, feature pitchers finishing twenty games over .500. You're just not going to do much better than that. Do that, and you had a historic season that is once a generation. Johnson was nearly 30 games over .500 at 36-7, with a 1.14 ERA, 20 complete games, 11 shutouts.
1920s: Babe Ruth, 1921
This is the first inarguable one. Ruth's best season, and probably the best year a baseball player has ever had. If it is not this year, it's one we are coming to.
1930s: Jimmie Foxx, 1932
The Beast. Double X. Actually, this could have easily gone to his teammate, pitcher Lefty Grove, for his 1931 season. Have a look at Grove's stats sometime, within the context of his era. You can argue that Grove is the best pitcher in baseball history. But how good was Foxx in 1932? His WAR was 10.5 to 8.3 of Ruth and 7.9 of Gehrig. 58 homers, 169 RBI, .364 BA, 151 runs, 438 total bases, 1.218 OPS.
1940s: Ted Williams, 1941
This one is easy. Williams hit .406. But his OBP was .553. That is one of the most insane stats in all of sports. That is a Little League stat for the biggest kid who also has a good eye. 1.287 OPS. No need to bring up DiMaggio in the same year because of his hitting streak. A hitting streak is one of the most overrated things in sport. It's a quirk, like when Mario Lemieux scored five goals five ways in 1988. It's like hitting for the cycle. Cool, but a novelty that requires skill. Besides, Williams hit for a higher average over the same 56 games.
1950s: Mickey Mantle, 1956
Also super easy--easier. Mantle's Triple Crown year. A weird-sounding remark at first: Mantle is underrated. He was a rich man's Mike Trout. In addition to his three MVPs, he was also the best player on the Yankees in 1960 and 1961, when Roger Maris won back-to-back MVPs. I have no problem with that. You break Ruth's home run record, you should be the MVP. That's part ceremonial, though.
1960s: Carl Yastrzemski, 1967
Your other choice is a Sandy Koufax season. I'd pick his 1963 campaign. But besides winning the Triple Crown, Yaz had a nutso clutch factor going. Basketball can have a one man team. A football team can be decent because of an amazing quarterback. In baseball, you shouldn't be able to be a one man team, and there were good players on those Sox, but it was largely a one man team. If you wanted, you could put together an argument for this being the best season ever. I wouldn't make it myself. This would be a big part of the core of your argument: Yaz's WAR of 12.5, with the second place finisher being at 7.7. Gaps like that are exceedingly rare.
1970s: Steve Carlton, 1972
This is a five person race. Jim Rice in 1978, George Foster in 1977, Rod Carew in 1977, Ron Guidry in 1978, and Carlton. That's the order I'd have them in from 5th to 1st. That Rice did not have an OPS over 1.000 is odd and a demerit. Foster was maybe a touch better, but that two guys were having basically the same exact year within a year of each other speaks, I think, to some trends of the time. Carew nearly hit .400, drove in a ton of runs, and had a higher OPS than Rice and was more dynamic in his season than Foster was in his. Guidry was 22 games over .500 and a WAR stud--he easily could have beaten Rice--who was third in WAR--for the 1978 AL MVP. But Carlton won 27 games on a team that won 59. They were awful. Yes, I know, wins are meaningless! But they are not. Every great pitcher between now and the 1860s has found ways to win. They make it work when they have little run support. Over the balance of a stretch of years, or a career, great pitchers always win a lot more than they lose, and I don't care if they normally play on lousy teams--this still holds true. But it's meaningless, right? There is no more slipshod logic in all of sports metrics right now than the braying insistence that wins do not matter for pitchers. Carlton also had 30 complete games and 8 shutouts. Oh. That's normal. His ERA was 1.97, with his 12.5 WAR being more than three wins higher than second place finisher Joe Morgan, not a bad little player himself--merely the game's greatest (or second greatest) all-time second baseman, during his prime as the best ballplayer on one of the best team's in history.
1980s: Roger Clemens, 1986
Clemens was arguably better in 1987--he led the league in WAR that year, nearly won the ERA crown, won 20 games, had 18 complete games, 7 shutouts, in a campaign when offense (1987 was easily the most fun season of the 1980s) was exploding, but 1986 was the signature season. The 14-0 start, the 20 K game, even the All-Star MVP. It was just one of those years for someone in American sport. George Brett in 1980 could be in this discussion, but he missed too much time. People are going to want to say Don Mattingly in 1985 and 1986, but go look up his WAR. Orel Hershiser in 1988 is another strong choice, but a stronger one would be Rickey Henderson in 1985. But what I'll call the second best season of the 1980s will surprise some people: Alan Trammell in 1987. The complete game, dominance in every five tool phase (if we substitute good base running for stolen bases).
1990s: Pedro Martinez, 1999
I'm not a huge Pedro guy. He didn't do it for long enough, he was never the main guy who made a team win--Curt Schilling was that guy in 2004, Martinez was the sidecar--and I like parts of his 1997 season with the Expos--he was more durable--than this Sox season. But any talk of Martinez's ERA in relation to his peers so dramatically settles the issue that I think it also settles the issue on best season of the 1990s. You would be tenth in the AL with a 4.12 ERA. Martinez's was half of that. Same thing basically happened the next season, and his ERA was actually a decent amount lower, but you recognize degrees of electricity, and Martinez's 1999 was to his 2000 as Clemens' 1986 was to his 1987. Part of me really prefers Greg Maddux's 1995.
2000s: Barry Bonds, 2004
You don't like him, he cheated, but I'm just going by what happened between the lines. Remember when I said that Babe Ruth's 1921 season is likely the best season in baseball history? Well, if it's not that one, it's this one. It is the most statistically singular, that's for sure. It is the most indicative of a player that the opposition had no game plan for, no means to cope with this level of greatness. Bonds walked 232 times. He had, consequently, 373 at bats, but enough plate appearances, easily, to qualify for the batting title, which he won by hitting .362. He hit 45 home runs. Do you know what that means if you hit that many home runs in that many at bats when you are walking that much? It means the other team is never giving you anything to hit, just about, and each time they kind of give you something to hit, you never miss it. You don't just never miss it, you drive it out of the park. His OBP was .609, and his OPS--this is almost funny--was 1.422. Best ever. Again, I don't know what you can even compare this season to statistically. It resembles no other season in baseball history.
2010s (thus far): Clayton Kershaw, 2014
If only he was better in the playoffs. Honorable mentions--pick a Mike Trout season, Mookie Betts in 2016, Justin Verlander in 2011, Miguel Cabrera in 2012.
So, what can we learn from this little exercise? OPS is a big deal. Wins matter for pitchers. The Los Angeles Dodgers have had matchless ace greatness over the years/generations. The Red Sox have had amazing front line talent, but the Yankees were stuffed with Hall of Fame players who can't make a list like this but were always among the top players in the league. They have been more consistently starred, you might say.