Every fall, as my birthday approaches, I repeat the same thing, mostly kidding: "my shot at being a pro athlete isn't over until I'm older than the average player!" I mean it for every sport, even though there's very little demand for 160 pound guys under 6 feet tall in any sport. This year, I can even sprinkle in that I'm about to be 27 - the age at which baseball players enter their prime - and promise that this is the year I can really break out (I've never even played baseball). I still maintain that I can hit a home run in batting practice (again, mostly kidding, but maybe not). If I was ever going to do it, it's now! I'm entering the prime of my career! I doubt I'll get a call from any Major League teams, but you never know - untested players entering their theoretical prime may be the new market inefficiency.
Thinking about my own age relative to baseball players got me thinking about the ages of actual players. Maybe some hit their stride a little late, like I still might. Others are joining the league right on schedule, but what that means for their careers is still to be determined. I ignored the players joining the Majors at unusually young ages, because the more of them there are, the less of a chance I have.
*** Late Bloomers: The Oldest Players to Have their Best Seasons Late in their Careers ***
The distribution of the best season (by fWAR) players have recorded by their age resembles the aging curve that has come to be accepted as common knowledge. Just like players tend to have their personal best seasons at age 27, with a rapid ramp before it and a slower decline after, most players have their career seasons at age 27, with fewer players having their career years prior and quite a few having career years in the seasons shortly after age 27.
However, there's a bit of a tail on the older age of the above chart; there are a small handful of players who posted career years in their late thirties. Over the last 37 years, about 20 veterans have had their best seasons after age 35. The 20 oldest of which are shown below, with one caveat:
The caveat: because our data runs from 1970 to 2017, we cut off the beginnings of careers of players whose careers began in the 1960s or before. I've done my best to weed out those instances by limiting this list to players with at least 5 seasons after 1970.
This list is full of pitchers, likely because good pitchers can reinvent themselves as relievers when they age past their usefulness as starting pitchers. For average starting pitchers, entering a late-season renaissance as a reliever gives them a chance to build up fWAR that compares favorably to their early- and mid-career fWAR. Interestingly, RA Dickey finds himself on this list not because of a successful transition to the bullpen, but because of a successful dedication to a new pitch. Dickey was middling at best up until he went all-in on the knuckleball, and gave the Mets a Cy Young Award performance in 2012 just a few years later.
The batters that had a late-career renaissance are an interesting group. Barry Bonds, like many of the pitchers on this list, reinvented himself and had what amounts to a second Hall of Fame career. Raul Ibanez put up his 3.4 fWAR in a shorter season, playing only 134 games but hitting a career high in home runs. Torii Hunter hit for more average than ever before and amassed better baserunning numbers. Like Ibanez and Hunter, Pete Rose simply had an unusually good year. Bonds was the only one to reinvent himself the way a pitcher might.
The Orioles only have a handful of players on the precipice of the latter half of their 30s, and only one is a regular starter. JJ Hardy has not gone about reinventing himself at the plate, and in fact his offensive play has slipped pretty dramatically. Unless Hardy becomes an even better defensive shortstop, it's unlikely that he will post his career best performance in the next few seasons. Among pitchers, Darren O'Day is the only one about to turn 35, and he's already been a very good reliever. H, in theory, has a chance to top his career best of 1.5 fWAR (amassed in 67 innings), if only because the Orioles continue to ask him to throw about that often during the season.
*** On Schedule: Expected Career Performance by 25-Year-Old Rookies ***
In the middle of the age spectrum are players who don't join the Majors very early or very late, the players who follow the script. For batters, this usually means a rookie season at age 25:
Most batters join the Majors for their first qualifying season between ages 23 and 27, with most rookies in the last (nearly) 40 years joining the Majors at age 25. After that age, the likelihood of making the big leagues seems to drop significantly for position players.
The 25-year-old rookie - seemingly the typical rookie - is an interesting one after 2017 for the Orioles. This season, the Orioles' own Trey Mancini made a splash at the Major League level as a 25-year-old rookie, and the team was introduced to the homer-happy face of one of their division rivals: 25-year-old Aaron Judge.
Early in the season, Mancini and Judge were frequently compared, as both were power-hitting rookie outfielders for their respective clubs, and fans from both teams felt that their breakout young player had a chance at end-of-season awards. Even today, Googling the names "Trey Mancini" and "Aaron Judge" together results in many asking questions about whether they should trade one for the other in fantasy baseball. The other result is telling of how the season progressed: Aaron Judge became the Next Big Thing, while Mancini continued to produce at a respectable clip while not maintaining his early-season breakneck pace.
Fans of both teams should feel fortunate to have quality young players, and a fair question is what to expect of them in the future. Since 1970, position players to debut at age 25 have produced wins with some consistency:
Among position players that reached the Majors at age 25, most realize a growth in fWAR over their first 3-4 seasons, then slowly taper off as they enter their mid-30s. The best stick around and continue to add 2-win value to their teams, while the others begin to retire.
In 2017, Trey Mancini's 1.8 fWAR was below the average for 25-year-old rookies in the last 37 years. He showed potential and the Orioles likely expect him to progress to providing 2- to 3-win value over the next few years. That would make Mancini a valuable and low cost member of the Baltimore Orioles. Aaron Judge, for comparison, put up an 8.2 fWAR season (hitting 52 home runs helps; ask Chris Davis). Judge is well above the average 25-year-old rookie, and pending a huge collapse, the Orioles can expect to have to deal with one of the game's best players for the foreseeable future.
To further illustrate the performance of Mancini and Judge relative to their 25-year-old rookie counterparts, we can look at a boxplot distribution of fWAR from 25-year-old rookie position players:
This is slightly more favorable to Mancini. It appears that the average fWAR from 25-year-old rookies is weighted up by the outliers like Aaron Judge, while the median performance is only just above what Mancini provided the Orioles in 2017. Mancini is well within the average range of players debuting at his age. Even if he's not Aaron Judge, Orioles fans should feel secure that the team has a capable young player who should produce in the outfield for some time.
