They say records are meant to be broken. This is usually true - but there are some of them out there in baseball that are nigh unbreakable. Climbing Mount Everest blindfolded without a Sherpa would be easier than usurping the holder of these records.
I'm using only MLB data here and ignoring any from the American Association. Given that the steroid era is likely in the rear view mirror, I debated about someone breaking Barry Bonds' 73 homers in a single season or his career home run total, but I think down the line, even though it may be decades from now, someone will surpass those totals.
Here is my list of the most unbreakable MLB records:
56 - Joe DiMaggio's 56-game Hit Streak
Unless there's some sort of radical overhaul in how pitching staffs are constructed - I don't see any hitter being able to stay as lucky as DiMaggio was with his streak. DiMaggio didn't have to worry about facing a relief specialist. He also didn't have to worry about flying across the country for games. There have been some who have made it to the high 30s or low 40s, but ultimately have crumbled. I see that trend continuing.
5,741 - Nolan Ryan's 5,714 Strikeouts
I think Ryan is a complete freak of nature who was able to stay healthy and throwing hard for far longer than many pitchers. Heck, he pitched as long as some knuckleballers. Randy Johnson finished nearly 1,000 K's behind Ryan. While hitters are striking out at a decent pace, the last pitcher to have over 300 strikeouts in a season was. Johnson. That was in 2002.
7 - Nolan Ryan's Seven No-hitters
I just can't see anyone ever having that combination of pure stuff, luck and longevity. Let's not forget, Ryan had two late-game no-hitters broken up by the same person in two weeks, so that number could have been an even more ridiculous nine.
1,406 - Rickey Henderson's 1,406 Career Stolen Bases
It would probably take yet another core shift in baseball philosophy to have anyone even come close to this total. Runners just aren't running willy-nilly on the bases anymore - partially due to the fact that pitchers have added an arsenal of ways to keep a baserunner close: slide steps, varied tempos in terms of delivering the ball to the plate and other tricks. Also, many teams prefer to go for the big inning rather than risk an out and losing a baserunner.
Let's put it this way - the closest active player to Henderson is Juan Pierre and he is on the downside of a career that has produced 574 stolen bases). Sadly, I do not see anyone in the future sliding into third base, ripping it out of the ground and proclaiming into a microphone that today they are the best basestealer of all time. Rickey was one of a kind.
130 - Rickey Henderson's 130 Single Season Stolen Base Mark
Again, it would like take a big philosophical change, plus the outlawing of the slide step. Players just aren't running as much. Case in point: After Henderson, the most stolen bases by an active player in a single season has been 78 by Jose Reyes. He'd have to steal 52 more bases on top of that. Behind Reyes, there's Jacoby Ellsbury with 70. Never mind that Ellsbury is having trouble staying on the field consistently. I really can't see this happening.
511 - Cy Young's 511 Career Wins
People are saying that there likely won't be another 300-game winner in the Majors again, so someone getting 211 more wins beyond that is about as likely as me being able to jump to the moon just using a pogo stick. Jamie Moyer, who has 269 wins, is also nearly 50 years old. Both Andy Pettitte and Roy Halladay are hurt this year and who knows when CC Sababthia's body will break down. Cy can rest very easy that no one will come within 100 miles of his total.
0.440 - Hugh Duffy's .440 Single Season Batting Average
It's been 71 years since Ted Williams even broke the .400 batting average and the closest any modern day player has come in a non-strike shortened season (Hi Tony Gwynn and your .394 average!) was George Brett in 1980 (.390). Rod Carew came a couple hits short of Brett's mark in '77, hitting .388. If someone hit .440 in a season, they'd also have to walk a ton to keep their plate appearances low, since as that rises, it's harder for a batting average to rise.
36 - Chief Wilsons' 36 Triples in a Season
Just for reference, Jose Reyes was considered a triples machine and he still fell 17 triples short in 2008. This year, the MLB league leader has five. Yes. 5. A triple is one of those things that needs a LOT to go right - a speedy runner, a ball caroming off the wall just the right way to scoot beyond the glove of an outfielder.
49 - Old Hoss Radburn's 49 Wins in a Season
I can't see a pitcher even coming close to Denny McClain's total of 31 wins let alone getting into Radburn's area. The most wins by a pitcher in the modern era was Bob Welch and he had 27 wins- 22 wins shy of Radburn. Welch essentially would have had to have two Cy Young winning seasons rolled into one. Even 20 wins are becoming more of a rarity with the 5-man pitching staff. The best a currently active player has done? Justin Verlander with 24. Barry Zito had 23 one year. Unless the managers decide to go back to a 4-man rotation or lift pitching or innings limits, there's no way any one will even sniff 30 wins, let along 49.
0.96 - Dutch Leonard's Single Season E.R.A. of 0.96
Dwight Gooden, Pedro Martinez and Greg Maddux each had seasons where they were the most dominating pitchers in the league. They still weren't as effective as Leonard was - he won 19 games and had a skimpy 0.96 ERA. The game as it is presently constructed heavily favors hitters over pitchers and I don't ever see a pitcher being that dominant again.
3,731 - Connie Mack's 3,731 Wins as a Manager
The reason this will never be broken is because Mack was one of the last owner/managers in baseball. He had partial ownership of the Philadelphia Athletics until 1937, when he gained full ownership. Since he never looked in the mirror and fired himself, he continued to manage the team until he was 87. How impregnable is this record? Tony La Russa, considered one of the best managers of this generation just retired - 1,003 wins shy of Mack.
Think any of these records will be broken or have a record not mentioned that won't be broken, let us know in the comments!