On the mound, at least, baseball is no longer an older man's game

What's interesting is the split that has developed between pitchers and hitters over the past few years. This season, 10 pitchers age 35 or over (as of June 30, the typical demarcation line for seasonal age) are holding down regular rotation spots. Another 20 have held significant roles in their team's bullpens, defined as appearing in at least 14 games, or about a third of the average team's schedule to date. Many of these pitchers are major contributors -- Mariano Rivera chugs along as the Yankees' closer at 41, with Kyle Farnsworth, 35, and Francisco Cordero, 36, saving games and posting solid ERAs. Bartolo Colon, 38, is one of the season's best stories, while Hiroki Kuroda, 36, is gaining ground on Hideo Nomo for the title of "best Japanese starter in Dodgers history."

Older batters are still getting playing time, but many seem to be in lineups as much because of contract status as performance. Twenty-five position players 35 or older have at least 120 plate appearances this season; of those, however, just seven are having productive seasons (eight if you care to classify Alfonso Soriano and his .291 OBP/.524 SLG in that group). For every Lance Berkman, leading the NL in SLG and OPS at age 35, there are two fading corner outfielders in the mold of Bobby Abreu (.258/.376/.327 at age 37) and Vladimir Guerrero (.298/.325/.429 at age 36).

"Old player" is a vague term, though, and maybe 35 isn't old. Draw the line at 37, and it really gets ugly. There are just 11 regulars 37 or older in the majors. Of those, only Chipper Jones, Jamey Carroll, Todd Helton and Ichiro Suzuki are having good years. There are just two regular starting pitchers in that age group, Colon and Derek Lowe, although there are also a number of relievers still contributing.

Let's look back a bit and pick a season, not necessarily at random, that helps to illustrate the change. In 2003 -- the year in which MLB instituted survey testing to help ascertain the level of PED use in its industry -- just seven players were regulars at age 37 or above. Their impact was significantly greater, however. This group included the NL MVP, Barry Bonds, at 38; Edgar Martinez hitting .294/.406/.489 at 40; Rafael Palmeiro hitting 38 home runs at 38 years old; and two every-day center fielders, Steve Finley and Craig Biggio. On the mound, a whopping nine pitchers 37 or older qualified for the ERA title, and 12 others made at least 50 relief appearances. Jamie Moyer won 20 games at 40 years old; Greg Maddux tied for the league lead in starts with 36, one fewer than his age; Kevin Brown posted a 2.39 ERA in a hitter's year.

Comparing the two seasons, it appears that for all the attention paid to the changes in the game, the biggest one is that older starting pitchers have all but disappeared. In 2003, pitchers age 40 or older made 109 starts and threw 939 1/3 innings. Last year they made 38 starts and threw 459 2/3 innings. This year, through a quarter of the schedule: three starts, 90 2/3 innings. Draw the line at 37 years old and you get more dramatic results; pitchers 37 and older made 339 starts back in '03; they made 103 last year, and have made just 24 this season.

Because of the attention paid to PEDs and their purported impact on the statistics of power hitters, we've spent a lot of time and energy looking for changes in hitters. The biggest change in the last few years, however, hasn't been in the batter's box, but on the mound. The older starting pitcher, the staple of the last decade, has moved to the brink of extinction. This is not necessarily connected with PEDs, although those who would see needles everywhere may wish to consider the ramifications of PED usage by pitchers -- largely ignored in the rush to indict home-run hitters for their successes -- may have affected the the aging process on the mound.

No, causes and effects are rarely so tidy. Baseball history is filled with these kinds of bumps; an extended stretch in which offense was near historical lows -- from 1963 through 1976, broadly -- allowed pitchers born in the 1940s to rack up large workloads while remaining healthy. Those pitchers created outsized expectations for the next generation, and caused many young arms to be abused, cutting short careers. Ron Guidry, Bret Saberhagen, Dwight Gooden, Dave Stieb -- the best pitchers born in the 1950s and 1960s -- had short, injury-plagued careers. Consider this: No pitcher born after 1951 has been elected to the Hall of Fame for his work as a starter, though Roger Clemens, Greg Maddux, Tom Glavine and Randy Johnson, all of whom were born between 1962 and 1966, will be appearing on the ballot starting in 2013. Those pitchers benefited from the five-man rotation and, as their careers wore on, from greater attention paid to pitch counts. Their longevity is in part due to the broken careers of the group that came before them.

That group is also a historical anomaly, however. In the same way that we had great catchers in the 1930s, great center fielders in the 1950s, great basestealers in the 1970s and great shortstops in the 1990s, we had a bounty of great pitchers come through in the 2000s. Talent doesn't distribute normally throughout history, and what we're seeing in 2011 -- the falloff in the impact of the aging starting pitcher -- hews closer to historical norms. Twenty years ago, the game looked like it does today: just 99 starts by pitchers age 37 or older. Go back 40 years, to 1971, and you find just 17 games started by pitchers that old (16 of them by a fading Jim Bunning).

The reasons are for history to decide. The data, though, tells the story: Pitching is no longer an old man's profession.